| 
                City, 
                State County Country  | 
            
                Intersection (Lat, Lng)  | 
            
                Type Status  | 
            Control Type / Other Control Type | Approaches / Driveways / ICD (m) | 
                Functional Class /  LaneType  | 
            Year Completed | Comments | 
|---|---|---|---|---|---|---|---|
| 
                Triangle,
                VA Prince William Co. United States  | 
            
                Kerill Rd. / Dondis Creek Ct. (38.54794, -77.31411)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 22.4177  | 
            
                Other (At-Grade) Single-Lane  |   
            2010 | Functional Class: Local ICD estimated from Google Maps linework. | 
| 
                Fairfax,
                VA Fairfax Co. United States  | 
            
                Patriot Cir. / Mason Pond Dr. (38.82981, -77.31152)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 42.6720  | 
            
                Other (At-Grade) Single-Lane  |   
            2008 | |
| 
                Linganore,
                MD Frederick Co. United States  | 
            
                Old National Pike / Eaglehead Dr. (39.38995, -77.31098)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 50.2920  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            2008 | South leg stubbed. Constructed initially as single-lane roundabout in 2007-2008. Expanded into two-lane roundabout 2016-2018. | 
| 
                Linganore,
                MD Frederick Co. United States  | 
            
                Lake Linganore Blvd. / Eaglehead Dr. (39.39732, -77.31047)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield Unknown  | 
            
                3 Approaches 1 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            2019 | Year Completed estimated (2018-2022). | 
| 
                Quantico Base,
                VA Prince William Co. United States  | 
            
                Barnett Ave. / Russell Rd. / Dunlap Rd. / Damato St. (38.51066, -77.31001)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            ||
| 
                New Market,
                MD Frederick Co. United States  | 
            
                Eaglehead Dr. / Pecking Stone St. (39.39397, -77.30943)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 24.3840  | 
            
                Other (At-Grade) Single-lane w/ Traversable Central Island  |   
            2016 | Year Completed estimated (2015-2017). | 
| 
                Hopewell,
                VA Hopewell City United States  | 
            
                Virginia St. / Wilmington Ave. (37.27664, -77.30884)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            Fire station in central island. | |
| 
                Prince George,
                VA Prince George Co. United States  | 
            
                Allin Rd. / A Ave. / Bull Hill Rd. / Jefferson Park Rd. (37.22679, -77.30860)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 32.3333  | 
            
                Other (At-Grade) Single-Lane  |   
            2012 | Right-turn-only lane on north leg. ICD estimated from Google Maps linework. | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Crestmount Rd. / Kings Crossing Rd. (39.16175, -77.30841)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            No splitter islands. | |
| 
                New Market,
                MD Frederick Co. United States  | 
            
                Eaglehead Dr. / Tomahawk St. / Fallfish Ct. (39.39677, -77.30826)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 35.0520  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            2018 | Year Completed estimated (2017-2018). | 
| 
                Ijamsville,
                MD Frederick Co. United States  | 
            
                Royal Saint Andrews Pl. / Quail Creek Pl. (39.38039, -77.30788)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Greenville,
                NC Pitt Co. United States  | 
            
                SR 2241 (Ivy Rd.) / SR 1774 (Mills Rd.) (35.52351, -77.30654)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield Unknown  | 
            
                4 Approaches 0 Driveways 39.8535  | 
            
                Other (At-Grade) Single-Lane  |   
            2015 | Project W-5601N. ICD estimated from Google Maps linework. | 
| 
                Linganore,
                MD Frederick Co. United States  | 
            
                Boyers Mill Rd. / Eaglehead Dr. (39.41912, -77.30650)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 33.5280  | 
            
                Other (At-Grade) Single-Lane  |   
            2018 | |
| 
                Boyds,
                MD Montgomery Co. United States  | 
            
                Crazy Quilt Ct. (39.16123, -77.30454)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            ||
| 
                Fairfax,
                VA City of Fairfax United States  | 
            
                University Dr. / (parking) (38.86028, -77.30428)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                2 Approaches 3 Driveways 27.4320  | 
            
                Other (At-Grade) Single-Lane  |   
            2022 | https://www.youtube.com/watch?v=UwmJSdActdk | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Kings Crossing Blvd. / Cornflower Rd. (39.16222, -77.30397)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            No splitter islands. | |
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Ashleigh Greene Rd. / Cornflower Rd. (39.15879, -77.30324)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            No splitter islands. | |
| 
                Oakton,
                VA Fairfax Co. United States  | 
            
                Hunter Mill Rd. / Mystic Meadow Way (38.88680, -77.30187)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 26.9599  | 
            
                Other (At-Grade) Single-Lane  |   
            2018 | ICD estimated from Google Maps linework. | 
| 
                Darnestown,
                MD Montgomery Co. United States  | 
            
                Schaeffer Rd. / Germantown Park Dr. / Central Park Cir. (39.15003, -77.30152)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 48.7680  | 
            
                Other (At-Grade) Single-Lane  |   
            2004 | Right-turn-only lane on northeast leg. Year Completed estimated (2002-2005). | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Crossview Rd. / Autumn Crest Rd. (39.16717, -77.30075)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            No splitter islands. | |
| 
                Ijamsville,
                MD Frederick Co. United States  | 
            
                Whiskey Rd. / Whiskey Ct. (39.36078, -77.30012)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Prince George,
                VA Prince George Co. United States  | 
            
                VA 106 (Courthouse Rd) / VA 634 (Allin Rd)  (37.22338, -77.29979)  | 
            
                Roundabout Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 38.0409  | 
            
                Other (At-Grade) Single-Lane  |   
            2010 | ICD estimated from Google Maps linework. | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Kings Crossing Blvd. / Ashmeade Rd. (39.16235, -77.29971)  | 
            
                Other Existing  | 
            
                All-Way Yield Unknown  | 
            
                3 Approaches 0 Driveways 32.0040  | 
            
                Other (At-Grade) Single-Lane  |   
            Painted splitter islands. Pedestrian crossings next to circulatory roadway. | |
| 
                (unincorporated),
                VA Henrico Co. United States  | 
            
                Darbytown Rd. / Turner Rd. (37.45112, -77.29935)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-lane w/ Traversable Central Island  |   
            2023 | Quick build with plastic central island. Peanut shaped. https://www.youtube.com/watch?v=3-AotYkeJqk | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Ashleigh Greene Rd. / Ashmeade Rd. (39.16013, -77.29900)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            No splitter islands. | |
| 
                Linganore,
                MD Frederick Co. United States  | 
            
                Mussetter Rd. / Whiterose Dr. / Whiterose Way (39.39008, -77.29747)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 41.1480  | 
            
                Other (At-Grade) Single-Lane  |   
            2002 | Painted splitter islands on three legs. Year Completed estimated (1988-2005). | 
| 
                Clarksburg,
                MD Montgomery Co. United States  | 
            
                Clarksburg Rd. / W Old Baltimore Rd. (39.21396, -77.29731)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 42.6720  | 
            
                Other (At-Grade) Single-Lane  |   
            2019 | Year Completed estimated (2019-2020). | 
| 
                New Market,
                MD Frederick Co. United States  | 
            
                Empire Blvd. / Edwardian Ln. / Jacobian Pl. (39.39428, -77.29567)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            Parking along circulatory roadway. | |
| 
                Linganore,
                MD Frederick Co. United States  | 
            
                Finn Dr. / Douglas Ave. / Huckleberry Way (39.40210, -77.29509)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            Pedestrian access to central island. No splitter islands. | |
| 
                Clarksburg,
                MD Montgomery Co. United States  | 
            
                Clarksburg Rd. (MD 121) / Cabin Branch Ave. (39.22689, -77.29051)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 46.2592  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            2015 | ICD estimated from Google Maps linework. | 
| 
                Woodbridge,
                VA Prince William Co. United States  | 
            
                Anchor Bend Circle (38.59517, -77.28977)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                2 Approaches 12 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Clarksburg,
                MD Montgomery Co. United States  | 
            
                Clarksburg Rd. (MD 121) / (outlet mall entrance) (39.22844, -77.28869)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 49.9588  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            2015 | ICD estimated from Google Maps linework. | 
| 
                Clarksburg,
                MD Montgomery Co. United States  | 
            
                Broadway Ave. / Little Seneca Pkwy. (39.21646, -77.28540)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield Unknown  | 
            
                3 Approaches 0 Driveways 45.7200  | 
            
                Other (At-Grade) Multilane (2 Lane, 2x2 max)  |   
            2016 | Year Completed estimated (2015-2017). Striping added 2019-2021. | 
| 
                Clarksburg,
                MD Montgomery Co. United States  | 
            
                Cabin Branch Ave. / Skimmer St. (39.22020, -77.28435)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield Unknown  | 
            
                4 Approaches 0 Driveways 45.7200  | 
            
                Other (At-Grade) Multilane (2 Lane, 2x2 max)  |   
            2016 | Year Completed estimated (2015-2017). Striping added 2019-2021. | 
| 
                Clarksburg,
                MD Montgomery Co. United States  | 
            
                Little Seneca Pkwy. / Cabin Branch Ave. (39.21654, -77.28310)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield Unknown  | 
            
                4 Approaches 0 Driveways 45.7200  | 
            
                Other (At-Grade) Multilane (2 Lane, 2x2 max)  |   
            2016 | Year Completed estimated (2016-2017). Striping added 2019-2021. | 
| 
                Woodbridge,
                VA Prince William Co. United States  | 
            
                Potomac Branch Dr. / Oberlin Dr. / Barkham Dr. / Weeburn Way / Cadbury Way (38.63114, -77.28082)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Shortsville,
                NY Ontario Co. United States  | 
            
                CR 28 / Shortsville Rd. (42.95597, -77.27692)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            2020 | https://www.democratandchronicle.com/story/news/2020/10/19/roundabout-opens-county-road-28-and-shortsville-road-farmington-ny/3706261001/ | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Kildale Hills Terrace / Galway Bay Cir. (39.17826, -77.27643)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Clarksburg,
                MD Montgomery Co. United States  | 
            
                Saint Clair Rd. / Timber Creek Ln. / Brewers Tavern Terrace / (unknown) (39.23680, -77.27531)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                5 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            No splitter islands. | |
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Wonderland Way / Chalet Dr. (39.15516, -77.27464)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            No splitter islands. | |
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Crystal Rock Dr. / Century Blvd. (39.20326, -77.27356)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 48.7680  | 
            
                Other (At-Grade) Multilane (2 Lane, 2x2 max)  |   
            2015 | Striping added 2019-2021. Inconsistent lane use markings between entry and circulatory roadway. | 
| 
                Oakton,
                VA Fairfax Co. United States  | 
            
                Saintsbury Dr. / (transit center parking garage) (38.87600, -77.27317)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 39.6240  | 
            
                Other (At-Grade) Single-Lane  |   
            2013 | Serves Metro station. Right-turn-only lanes on northeast and southwest legs. Southeast leg stubbed. Year Completed estimated (2012-2014). | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Pickering Dr. / Pickering Pl. (39.18854, -77.27173)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Club Hill Dr. / Thackery Pl. (39.18531, -77.27012)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Oakton,
                VA Fairfax Co. United States  | 
            
                Saintsbury Dr. / (transit center parking lot) (38.87667, -77.26993)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 35.0520  | 
            
                Other (At-Grade) Single-Lane  |   
            2013 | Serves Metro station. Right-turn-only lanes on east and west legs. South leg stubbed. Year Completed estimated (2012-2014). | 
| 
                Oakton,
                VA Fairfax Co. United States  | 
            
                Nutley St. SW / I-66 WB Exit Ramp (38.87982, -77.26743)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Freeway Ramps (Grade-Separated) Multilane (2 Lane, 2x1 max)  |   
            2023 | Replaces full cloverleaf interchange. https://outside.transform66.org/about_the_project/project_sections/nutley.asp | 
| 
                Clarksburg,
                MD Montgomery Co. United States  | 
            
                Granite Rock Rd. / Grand Elm St. (39.24126, -77.26647)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            No splitter islands. | |
| 
                Oakton,
                VA Fairfax Co. United States  | 
            
                Nutley St. SW / I-66 EB Exit Ramp (38.87714, -77.26629)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Freeway Ramps (Grade-Separated) Multilane (2 Lane, 2x1 max)  |   
            2023 | Replaced full cloverleaf interchange. https://outside.transform66.org/about_the_project/project_sections/nutley.asp | 
| 
                Vienna,
                VA Fairfax Co. United States  | 
            
                Park St. SE / Locust St. SE (38.90205, -77.26091)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 14.8712  | 
            
                Other (At-Grade) Single-lane w/ Traversable Central Island  |   
            2018 | Year Completed estimated (2016-2018). ICD estimated from Google Maps linework. | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Milestone Manor Ln. / Royal Crown Dr. (39.20518, -77.25877)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                (unincorporated),
                MD Montgomery Co. United States  | 
            
                Travilah Rd. / Turkey Foot Rd. / Hanson Farm Dr. (39.07993, -77.25560)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 33.5280  | 
            
                Other (At-Grade) Single-Lane  |   
            2020 | Painted splitter islands. Year Completed estimated (2019-2020). | 
| 
                Clarksburg,
                MD Montgomery Co. United States  | 
            
                Little Seneca Pkwy. / Snowden Farm Pkwy. (39.22989, -77.25280)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 28.6795  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            2012 | Year Completed estimated (2011-2013). ICD estimated from Google Maps linework. | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Milestone Manor Ln. / Emerald Dr. (39.20479, -77.25262)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Milestone Manor Ln. / Stardrift Dr. (39.20560, -77.25039)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Milestone Manor Ln. / Manor View Cir. / Milestone Manor Ct. (39.20854, -77.24868)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Clarksburg,
                MD Montgomery Co. United States  | 
            
                Snowden Farm Pkwy. / Winding Woods Way (39.22604, -77.24727)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 40.7086  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            2012 | Year Completed estimated (2011-2013). ICD estimated from Google Maps linework. | 
| 
                Canandaigua,
                NY Ontario Co. United States  | 
            
                CR 10 / CR 4 (42.90187, -77.24570)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 33.2451  | 
            
                Other (At-Grade) Single-Lane  |   
            2013 | ICD estimated from Google Maps linework. | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Observation Dr. / Goldenrod Ln. (39.18419, -77.24566)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 45.7200  | 
            
                Other (At-Grade) Multilane (2 Lane, 2x2 max)  |   
            2013 | Year Completed estimated (2012-2014). | 
| 
                Canandaigua,
                NY Ontario Co. United States  | 
            
                CR 10 / CR 46 (42.88665, -77.24563)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 31.5031  | 
            
                Other (At-Grade) Single-Lane  |   
            2013 | ICD estimated from Google Maps linework. | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Summer Oak Dr. / Summer Oak Ct. (39.16467, -77.24384)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            No splitter islands on two legs. | |
| 
                Clarksburg,
                MD Montgomery Co. United States  | 
            
                Little Seneca Pkwy. / Meadow Mist Rd. (39.23154, -77.24309)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 30.5290  | 
            
                Other (At-Grade) Single-Lane  |   
            2011 | ICD estimated from Google Maps linework. | 
| 
                Gaithersburg,
                MD Montgomery Co. United States  | 
            
                Kentlands Blvd. / Main St. (39.12333, -77.23855)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 42.6720  | 
            
                Other (At-Grade) Multilane (2 Lane, 2x1 max)  |   
            1994 | Year Completed estimated (1993-2002). | 
| 
                Woodbridge,
                VA Prince William Co. United States  | 
            
                Belmont Bay Dr. / Palisades St. (38.65612, -77.23753)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 35.4412  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            2000 | ICD estimated from Google Maps linework. | 
| 
                Woodbridge,
                VA Prince William Co. United States  | 
            
                Belmont Bay Dr. / Course View Way (38.65403, -77.23640)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 25.1826  | 
            
                Other (At-Grade) Single-Lane  |   
            2000 | ICD estimated from Google Maps linework. | 
| 
                Gaithersburg,
                MD Montgomery Co. United States  | 
            
                Kentlands Blvd. / Market St. (39.12309, -77.23489)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 41.1480  | 
            
                Other (At-Grade) Multilane (2 Lane, 2x1 max)  |   
            1994 | Year Completed estimated (1993-2002). | 
| 
                Travilah,
                MD Montgomery Co. United States  | 
            
                Marwood Hill Dr. / Rivers Bend Ln. (39.03022, -77.23432)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            ||
| 
                Gettysburg,
                PA Adams Co. United States  | 
            
                Lincoln Square (Chamberburg St. / York St. / Carlisle St. / Baltimore St.) (39.83092, -77.23112)  | 
            
                Other Existing  | 
            
                All-Way Yield Unknown  | 
            
                4 Approaches 0 Driveways 31.1838  | 
            
                Other (At-Grade) Single-Lane  |   
            Diagonal parking around circulatory roadway; pedestrian access to center island; no splitter islands. ICD estimated from Google Maps linework. | |
| 
                Canandaigua,
                NY Ontario Co. United States  | 
            
                CR 46 / Smith Rd. (42.88614, -77.22771)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 42.6720  | 
            
                Other (At-Grade) Single-Lane  |   
            2022 | Year Completed estimated (2020-2023). | 
| 
                Gaithersburg,
                MD Montgomery Co. United States  | 
            
                Winter Walk Dr. / Highland Ridge Ave. (39.12807, -77.22692)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 34.2800  | 
            
                Other (At-Grade) Single-Lane  |   
            1998 | Year Completed estimated (1993-2002). Was cul-de-sac prior to addition of two more legs. ICD estimated from Google Maps linework. | 
| 
                Gaithersburg,
                MD Montgomery Co. United States  | 
            
                Orchard Ridge Dr. / Mill Green Ave. (39.12559, -77.22635)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 37.9872  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            2002 | ICD estimated from Google Maps linework. | 
| 
                Gaithersburg,
                MD Montgomery Co. United States  | 
            
                Parkview Ave. / Uptown St. (39.15334, -77.22619)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 36.5760  | 
            
                Other (At-Grade) Single-Lane  |   
            2012 | Right-turn-only lane on northwest leg. Year Completed estimated (2011-2012). | 
| 
                Germantown,
                MD Montgomery Co. United States  | 
            
                Germantown Rd. / Watkins Mill Rd. / Blunt Rd. (39.19058, -77.22492)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 36.5760  | 
            
                Other (At-Grade) Single-Lane  |   
            1999 | Right-turn bypass lane on north leg. Year Completed estimated (1993-2005). | 
| 
                Gaithersburg,
                MD Montgomery Co. United States  | 
            
                Upshire Circle (39.11353, -77.22397)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Potomac,
                MD Montgomery Co. United States  | 
            
                Brickyard Rd. / Brent Rd. (38.99900, -77.22362)  | 
            
                Traffic Calming Circle Existing  | 
            
                One-Way/Two-Way Stop Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            ||
| 
                Potomac,
                MD Montgomery Co. United States  | 
            
                10600 Morning Field Dr. / Sunny Brooke Ln. / Sunny Brooke Pl. (39.07423, -77.21561)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Potomac,
                MD Montgomery Co. United States  | 
            
                Brickyard Rd. / Hackamore Dr. (38.98567, -77.21274)  | 
            
                Traffic Calming Circle Existing  | 
            
                One-Way/Two-Way Stop Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            ||
| 
                Potomac,
                MD Montgomery Co. United States  | 
            
                Brickyard Rd. / Horseshoe Ln. (38.99291, -77.21195)  | 
            
                Traffic Calming Circle Existing  | 
            
                One-Way/Two-Way Stop Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            ||
| 
                Gaithersburg,
                MD Montgomery Co. United States  | 
            
                Perry Pkwy. / (parking) (39.14899, -77.21048)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 47.2440  | 
            
                Other (At-Grade) Multilane (2 Lane, 2x1 max)  |   
            2004 | Year Completed estimated (2002-2005). | 
| 
                Rockville,
                MD Montgomery Co. United States  | 
            
                Valley Dr. / Aqua Ln. (39.07945, -77.20575)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            ||
| 
                Gaithersburg,
                MD Montgomery Co. United States  | 
            
                Washingtonian Blvd. / Washington Blvd. (39.11773, -77.20314)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 36.5760  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            1998 | Year Completed estimated (1993-2002). | 
| 
                Gaithersburg,
                MD Montgomery Co. United States  | 
            
                Washingtonian Blvd. / Rio Blvd. (39.11678, -77.20122)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 36.5760  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            1998 | Year Completed estimated (1993-2002). | 
| 
                North Potomac,
                MD Montgomery Co. United States  | 
            
                Bald Cypress Dr. / Willow Tree Dr. / Cherrydale Dr. (39.08158, -77.20120)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            ||
| 
                Annandale,
                VA Fairfax Co. United States  | 
            
                Ravensworth Rd. / Jayhawk St. / Fountain Head Dr. (38.82630, -77.19993)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield Unknown  | 
            
                4 Approaches 0 Driveways 22.8600  | 
            
                Other (At-Grade) Single-lane w/ Traversable Central Island  |   
            2018 | Modular, rapid-install roundabout. | 
| 
                Potomac,
                MD Montgomery Co. United States  | 
            
                Broad Green Dr. / Clagett Farm Dr. (39.04566, -77.19669)  | 
            
                Other Existing  | 
            
                All-Way Yield Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            ||
| 
                Carlisle,
                PA Cumberland Co. United States  | 
            
                N College St. / B St. (40.20962, -77.19535)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            2022 | https://www.youtube.com/watch?v=KwvSjWacVwI | 
| 
                Carlisle,
                PA Cumberland Co. United States  | 
            
                B St. / Fairground Ave. (40.20914, -77.18946)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            2022 | https://www.facebook.com/carlislepa/videos/b-street-and-fairground-avenue-roundabout/587170292764586/ | 
| 
                Gaithersburg,
                MD Montgomery Co. United States  | 
            
                Victory Farm Dr. / Girard St. (39.14648, -77.18493)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 25.9348  | 
            
                Other (At-Grade) Multilane (2 Lane, unspecified)  |   
            2006 | Year Completed estimated (2005-2006). ICD estimated from Google Maps linework. | 
| 
                Picton,
                ON Prince Edward Canada  | 
            
                Loyalist Pkwy. / Sandy Hook Rd. (43.99449, -77.17838)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 40.3828  | 
            
                Other (At-Grade) Single-Lane  |   
            2009 | This was the first highway roundabout in Ontario. Constructed in 2009. https://www.auto123.com/en/news/ontarios-first-roundabout-intersection-opens-near-picton/5652/ ICD estimated from Google Maps linework. | 
| 
                King Farm,
                MD Montgomery Co. United States  | 
            
                Pleasant Circle (39.11623, -77.17518)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            Pedestrian access to central island. | |
| 
                Potomac,
                MD Montgomery Co. United States  | 
            
                Larkmeade Ln. / Bells Ridge Dr. (39.03483, -77.16775)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Rockville,
                MD Montgomery Co. United States  | 
            
                Henderson Circle (39.08800, -77.16702)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            Pedestrian access to central island. | |
| 
                Shermans Dale,
                PA Perry Co. United States  | 
            
                SR 34-SR 850 (Spring Rd.) / SR 34 (Spring Rd.) / SR 850 (Valley Rd.) / Pisgah State Rd. (40.31955, -77.16513)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 33.5280  | 
            
                Other (At-Grade) Single-Lane  |   
            2021 | |
| 
                Redland,
                MD Montgomery Co. United States  | 
            
                Columbus Ave. / Gramercy Blvd. (39.12362, -77.16494)  | 
            
                Other Existing  | 
            
                All-Way Stop Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            ||
| 
                Potomac,
                MD Montgomery Co. United States  | 
            
                Old Seven Locks Rd. / Quarry Manor Terrace (38.99371, -77.16028)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                3 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Single-Lane  |   
            No splitter islands. | |
| 
                Taneytown,
                MD Carroll Co. United States  | 
            
                MD 140 / MD 832 / Antrim Blvd. (39.64809, -77.15468)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                4 Approaches 0 Driveways 44.1960  | 
            
                Other (At-Grade) Single-Lane  |   
            1996 | Completed August 1996. Curbs set for double lane, striped for single outer circulating lane. | 
| 
                Cooksville,
                MD Howard Co. United States  | 
            
                Long Corner Rd. / Penn Shop Rd. (39.33938, -77.15284)  | 
            
                Roundabout Existing  | 
            
                All-Way Yield None  | 
            
                3 Approaches 0 Driveways 28.9560  | 
            
                Other (At-Grade) Single-Lane  |   
            2005 | Year Completed estimated (1988-2005). | 
| 
                Potomac Heights,
                MD Charles Co. United States  | 
            
                Cedar Ln. / Glymont Rd. / Greenwood Pl. (38.60764, -77.14063)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                4 Approaches 0 Driveways 0.0000  | 
            
                Other (At-Grade) Unknown  |   
            ||
| 
                Callao,
                Constitutional Province of Callao Constitutional Province of Callao Peru  | 
            
                Plaza Garabaldi (-12.05221, -77.13904)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                5 Approaches 0 Driveways  | 
            
                Other (At-Grade) Multilane (3+ Lane)  |   
            ||
| 
                Callao,
                Callao Callao Peru  | 
            
                Calle Comandante Juan Fanning [Avenida República de Argentina / Avenida República de Panamá / Avenida Contralmirante Mora] (-12.05156, -77.13409)  | 
            
                Other Existing  | 
            
                Uncontrolled None  | 
            
                4 Approaches 0 Driveways  | 
            
                Other (At-Grade) Multilane (3+ Lane)  |   
            ||
| 
                Callao,
                Constitutional Province of Callao Constitutional Province of Callao Peru  | 
            
                Plaza Guardia Chalaca (-12.06804, -77.13347)  | 
            
                Other Existing  | 
            
                Unknown Unknown  | 
            
                7 Approaches 0 Driveways  | 
            
                Other (At-Grade) Unknown  |