Roundabouts Database Index

29465 Results

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City, State County Country	Intersection (Lat, Lng)	Type Status	Control Type / Other Control Type	Approaches / Driveways / ICD (m)	Functional Class / LaneType	Year Completed	Comments
Columbia, MD Howard Co. United States	Banneker Rd. / Cul-de-sac (39.21141, -76.87041)	Traffic Calming Circle Existing	Unknown Unknown	3 Approaches 0 Driveways 17.5824	Other (At-Grade) Single-Lane		Functional Class: Local ICD estimated from Google Maps linework.
Columbia, MD Howard Co. United States	Trotter Rd. / South Wind Cir. (39.20956, -76.91891)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 23.1353	Other (At-Grade) Single-Lane	1997	Functional Class: Collector. Year Completed estimated (1993-2001). ICD estimated from Google Maps linework.
(unincorporated), MD Anne Arundel Co. United States	Arundel Beach Rd. / Leelyn Dr. (39.07955, -76.54560)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 25.9594	Other (At-Grade) Single-Lane	1999	ICD estimated from Google Maps linework.
Brunswick, MD Frederick Co. United States	MD 17 / A St. / B St. / Maryland Ave. (39.31433, -77.62807)	Roundabout Existing	All-Way Yield None	5 Approaches 0 Driveways 42.5054	Other (At-Grade) Single-Lane	2000	ICD estimated from Google Maps linework.
Mount Rainier, MD Prince Georges Co. United States	US 1 / 34th St. / Perry St. (38.93647, -76.96074)	Roundabout Existing	All-Way Yield None	5 Approaches 0 Driveways 41.1480	Other (At-Grade) Multilane (2 Lane, 2x1 max)	2001	Oval shaped. ICD = 135 ft x 115 ft.
Lutherville-Timonium, MD Baltimore Co. United States	MD 139 (Charles St.) / Bellona Ave. (39.41790, -76.62900)	Roundabout Removed	All-Way Yield None	4 Approaches 0 Driveways 28.9560	Other (At-Grade) Multilane (2 Lane, unspecified)	1999	Two-lane circulatory roadway across northern half.
Abingdon, MD Harford Co. United States	Tollgate Rd. / Montrose Way (39.48198, -76.32751)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 28.5762	Other (At-Grade) Single-Lane	2003	Elementary school and library to north, another school to south. Functional Class: Collector ICD estimated from Google Maps linework.
Bel Air, MD Harford Co. United States	Tollgate Rd. / Westover Ln. / Crisfield Dr. (39.46859, -76.32162)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 26.7377	Other (At-Grade) Single-Lane	2002	http://www.teachamerica.com/roundabouts/RA058B_ppr_Statmeyer.pdf#search=%22bel%20air%20roundabout%22 Previously controlled by two-way stop Functional Class: Collector ICD estimated from Google Maps linework.
Ritchie, MD Prince Georges Co. United States	Ritchie-Marlboro Rd. / I-95 SB Ramps (38.86894, -76.84738)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 770.9968	Freeway Ramps (Grade-Separated) Multilane (3+ Lane)	2001	Opening initially with two lanes. Expanded from two lanes to three lanes in 2010. 21442
Ritchie, MD Prince Georges Co. United States	Ritchie-Marlboro Rd. / I-95 NB Ramps (38.86824, -76.84158)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 67.0560	Freeway Ramps (Grade-Separated) Multilane (3+ Lane)	2001	Opened initially with two lanes. Expanded from two lanes to three lanes in 2010. 21442
Catonsville, MD Baltimore Co. United States	MD 372 / Hilltop Rd. / Entrance to UMBC (39.25733, -76.71964)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 35.1417	Other (At-Grade) Single-Lane	1998	Functional Class: Collector ICD estimated from Google Maps linework.
Lisbon, MD Howard Co. United States	MD 94 / Old Frederick Rd. (Lisbon North) (39.34810, -77.06930)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 26.7839	Other (At-Grade) Single-Lane	1999	ICD estimated from Google Maps linework.
Ellicott City, MD Howard Co. United States	MD 103 / MD 100 WB Ramps (39.20846, -76.78294)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 33.3154	Freeway Ramps (Grade-Separated) Single-Lane	1998	Opened November 1998. ICD estimated from Google Maps linework.
Ellicott City, MD Howard Co. United States	MD 103 / MD 100 EB Ramps (39.20733, -76.78243)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 30.5396	Freeway Ramps (Grade-Separated) Single-Lane	1998	Opened November 1998. ICD estimated from Google Maps linework.
Ellicott City, MD Howard Co. United States	Snowden River Pkwy. / MD 100 WB Ramps (39.21233, -76.79544)	Roundabout Existing	All-Way Yield Metering Signal	3 Approaches 0 Driveways 25.9105	Freeway Ramps (Grade-Separated) Single-Lane	1998	Opened November 1998. Metering signal on Snowden River Pkwy approach. ICD estimated from Google Maps linework.
Ellicott City, MD Howard Co. United States	MD 104 (Waterloo Rd.) / MD 100 WB Ramps (39.22470, -76.80600)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 45.7200	Freeway Ramps (Grade-Separated) Multilane (2 Lane, 2x2 max)	1999
Federalsburg, MD Caroline Co. United States	MD 307 / MD 313 / MD 318 (38.68938, -75.78949)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 35.4247	Other (At-Grade) Single-Lane	1999	Rural, installed for safety reasons Previously controlled by two-way stop ICD estimated from Google Maps linework.
Annapolis, MD Anne Arundel Co. United States	Gateway Circle [MD 450 (West St.) / Taylor Ave. / Spa Rd.] (38.97630, -76.50486)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 54.8640	Other (At-Grade) Multilane (2 Lane, unspecified)	1999	Elliptical shaped. ICD = 180 ft x 160 ft. Opened December 1999.
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.
Lisbon, MD Howard Co. United States	MD 94 / MD 144 (39.33700, -77.07360)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 30.4800	Other (At-Grade) Single-Lane	1993	First roundabout in Maryland. Built initially as temporary, made permanent after one month.
Lothian, MD Anne Arundel Co. United States	MD 2 / MD 408 / MD 422 (38.82973, -76.61590)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 28.8423	Other (At-Grade) Single-Lane	1995	Completed October 1995. ICD estimated from Google Maps linework.
Elkton, MD Cecil Co. United States	MD 213 (Fair Hill Rd.) / Leeds Rd. / Elk Mill Rd. (Lanzi Circle) (39.66364, -75.85529)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 34.0178	Other (At-Grade) Single-Lane	1995	Previously controlled by two-way stop. Functional Class: Arterial ICD estimated from Google Maps linework.
Cearfoss, MD Washington Co. United States	MD 63 / MD 58 / MD 494 (Cearfoss Pike) (39.70017, -77.77593)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 35.0520	Other (At-Grade) Single-Lane	1995	Completed December 1995.
Towson, MD Baltimore Co. United States	MD 45 / MD 146 / Joppa Rd. / Allegheny Ave. (39.40185, -76.60230)	Roundabout Existing	All-Way Yield None	5 Approaches 0 Driveways 47.9892	Other (At-Grade) Multilane (2 Lane, unspecified)	1998	Opened October 1998. Exit striping retrofitted to roundabout after opening. Hotdog/racetrack shape. ICD estimated from Google Maps linework. 21442
Ellicott City, MD Howard Co. United States	Rogers Ave / Old Frederick Road (39.29904, -76.81308)	Roundabout Existing	All-Way Yield None	3 Approaches 1 Driveways 26.8026	Other (At-Grade) Single-Lane	2004	ICD estimated from Google Maps linework. Old Frederick Road is MD 985A but roundabout may be locally maintained and not state maintained
Baltimore, MD Baltimore City Co. United States	Guilford Ave. / 22nd St. (39.31441, -76.61263)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 6.4682	Other (At-Grade) Single-lane w/ Traversable Central Island	2012	ICD estimated from Google Maps linework.
Baltimore, MD Baltimore City Co. United States	Guilford Ave. / E 24th St. (39.31650, -76.61276)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 9.2400	Other (At-Grade) Single-lane w/ Traversable Central Island	2012	ICD estimated from Google Maps linework.
Baltimore, MD Baltimore City Co. United States	Guilford Ave. / E 32nd St. (39.32703, -76.61345)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways	Other (At-Grade) Single-lane w/ Traversable Central Island	2012
Catonsville, MD Baltimore Co. United States	Edmundson Avenue / Old Frederick Road (39.27533, -76.76612)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 20.3400	Other (At-Grade) Single-Lane	2010	ICD estimated from Google Maps linework.
Brunswick, MD Frederick Co. United States	MD 17 / Rosemont Drive / Dutchmans Creek (39.33480, -77.63671)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 43.4167	Other (At-Grade) Multilane (2 Lane, unspecified)	2010	ICD estimated from Google Maps linework.
Brunswick, MD Frederick Co. United States	MD 17 / Volunteer Drive (39.33261, -77.63365)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 36.9516	Other (At-Grade) Multilane (2 Lane, unspecified)	2010	ICD estimated from Google Maps linework.
Brunswick, MD Frederick Co. United States	Potomac View Parkway / Dutchmans Creek (39.33265, -77.63770)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 32.3326	Other (At-Grade) Single-Lane	2010	ICD estimated from Google Maps linework.
Brunswick, MD Frederick Co. United States	Potomac View Parkway / Volunteer Drive (39.33145, -77.63483)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 34.1808	Other (At-Grade) Single-Lane	2010	ICD estimated from Google Maps linework.
Baltimore, MD Baltimore City Co. United States	Old Frederick Road / Maple Wood Road (39.29094, -76.69283)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 25.8815	Other (At-Grade) Single-Lane	2013	4th leg not built yet - for future development ICD estimated from Google Maps linework.
Baltimore, MD Baltimore City Co. United States	Wilkens Ave / Mount St / Ramsey St (39.28325, -76.64332)	Roundabout Existing	All-Way Yield None	5 Approaches 0 Driveways 31.4310	Other (At-Grade) Single-Lane	2001	Completed prior to 2002 ICD estimated from Google Maps linework.
Baltimore, MD Baltimore City Co. United States	Canterbury Rd. / W 39th St. (39.33569, -76.62047)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 16.6275	Other (At-Grade) Single-lane w/ Traversable Central Island	2013	ICD estimated from Google Maps linework.
Elkridge, MD Howard Co. United States	Elkridge Crossing Way / Doctor Patel Dr. (39.21091, -76.72512)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 31.4634	Other (At-Grade) Single-Lane	2007	East leg stubbed for future. ICD estimated from Google Maps linework.
Essex, MD Baltimore Co. United States	Southeast Blvd. (MD 702) / Hyde Park Rd. (39.29884, -76.43951)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 40.6663	Other (At-Grade) Multilane (2 Lane, unspecified)	2006	Built as temporary installation, then converted to permanent design. ICD estimated from Google Maps linework.
Owings Mills, MD Baltimore Co. United States	Tollgate Rd. / Lastgage Rd. (39.42149, -76.78482)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 28.6010	Other (At-Grade) Single-Lane	2004	ICD estimated from Google Maps linework.
Sykesville, MD Carroll Co. United States	Smithfield Ave. / Warfield Ave. (39.37673, -76.96410)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 47.0835	Other (At-Grade) Multilane (2 Lane, unspecified)	2007	Elliptical shape. ICD estimated from Google Maps linework.
Bowie, MD Prince George's Co. United States	Melford Blvd. / Science Dr. (38.96089, -76.71320)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 43.6480	Other (At-Grade) Multilane (2 Lane, unspecified)	2008	Concentric striping in circulatory roadway. ICD estimated from Google Maps linework.
Bowie, MD Prince George's Co. United States	Melford Blvd. / Curie Dr. (38.95842, -76.70683)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 78.9406	Other (At-Grade) Single-Lane	2008	ICD estimated from Google Maps linework.
Abingdon, MD Harford Co. United States	Merchants Blvd. / Wegmans Blvd. (39.46815, -76.30901)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 29.5039	Other (At-Grade) Single-Lane	2012	ICD estimated from Google Maps linework.
Laurel, MD Howard Co. United States	Whiskey Bottom Rd. / All Saints Rd. (39.12478, -76.84257)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 25.9428	Other (At-Grade) Single-Lane	2007	ICD estimated from Google Maps linework.
Laurel, MD Howard Co. United States	Stephens Rd. / Whiskey Bottom Rd. (39.12704, -76.84608)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 29.6480	Other (At-Grade) Single-Lane	2005	ICD estimated from Google Maps linework.
Gambrills, MD Anne Arundel Co. United States	2498 Mt Tabor Rd (38.99855, -76.66414)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 22.2765	Other (At-Grade) Single-Lane	2007	ICD estimated from Google Maps linework.
Greenbelt, MD Prince George's Co. United States	Cherrywood Ln. / Greenbelt Metro Dr. (39.00985, -76.90330)	Roundabout Existing	All-Way Yield Other	3 Approaches 0 Driveways 24.1290	Other (At-Grade) Single-Lane	2012	Raised crosswalks. ICD estimated from Google Maps linework.
Havre de Grace, MD Harford Co. United States	Chapel Rd. / Bulle Rock Pkwy. (39.55465, -76.12813)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 34.9922	Other (At-Grade) Single-Lane	2005	ICD estimated from Google Maps linework.
Havre de Grace, MD Harford Co. United States	Blenheim Farm Ln. / Bounding Home Ct. (39.54665, -76.13521)	Other Existing	All-Way Yield None	4 Approaches 0 Driveways 30.3915	Other (At-Grade) Single-Lane	2006	Painted splitter islands on north and south legs, no splitter islands on east and west legs. ICD estimated from Google Maps linework.
North East, MD Cecil Co. United States	Charlestown Crossing Blvd. / Claiborne Rd. (39.59472, -75.97957)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 27.6095	Other (At-Grade) Single-Lane	2011	ICD estimated from Google Maps linework.
Dundalk, MD Baltimore Co. United States	Dundalk Ave. / Sollers Point Rd. (39.24534, -76.50786)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 24.9734	Other (At-Grade) Single-Lane	2007	ICD estimated from Google Maps linework.
North East, MD Cecil Co. United States	Seahawk Dr. / (parking lot) (39.64098, -75.95714)	Roundabout Existing	All-Way Yield None	3 Approaches 1 Driveways 28.5107	Other (At-Grade) Single-Lane	2000	Year Completed estimated (1995-2005). ICD estimated from Google Maps linework.
Hampstead, MD Carroll Co. United States	MD 30 (Hampstead Bypass) / Business MD 30 (Hanover Pike) (39.58178, -76.84261)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 56.1498	Other (At-Grade) Multilane (2 Lane, unspecified)	2009	ICD estimated from Google Maps linework.
Hampstead, MD Carroll Co. United States	MD 30 (Hampstead Bypass) / MD 482 (Hampstead Mexico Rd.) (39.61108, -76.86457)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 53.3657	Other (At-Grade) Multilane (2 Lane, unspecified)	2009	ICD estimated from Google Maps linework.
Hampstead, MD Carroll Co. United States	MD-30 (Hampstead Bypass) / Business MD 30 (Hanover Pike) (39.63466, -76.86675)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 49.6684	Other (At-Grade) Multilane (2 Lane, unspecified)	2009	ICD estimated from Google Maps linework.
Windsor Mill, MD Baltimore Co. United States	Lord Baltimore Dr. / Wildlife Dr. (39.31993, -76.75019)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 14.7833	Other (At-Grade) Single-Lane	1998	Year Completed estimated (1993-2002). ICD estimated from Google Maps linework.
Windsor Mill, MD Baltimore Co. United States	Lord Baltimore Dr. / Glen Spring Rd. / Kettle Ct. (39.31750, -76.75152)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 17.5558	Other (At-Grade) Single-Lane	1998	Year Completed estimated (1993-2002). ICD estimated from Google Maps linework.
Queenstown, MD Queen Anne's Co. United States	Nesbit Rd. / Shoreway Dr. (38.96600, -76.18291)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways	Other (At-Grade) Single-Lane	2011	Fourth leg stubbed.
Cumberland, MD Allegany Co. United States	US 220 / I-68 EB Ramps (39.64367, -78.79099)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 34.0276	Freeway Ramps (Grade-Separated) Single-Lane	2012	Built to facilitate U-turns. Teardrop shape. ICD estimated from Google Maps linework.
Chestertown, MD Kent Co. United States	MD 20 / MD 291 / (parking lot) (39.21863, -76.07913)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 47.1899	Other (At-Grade) Single-Lane	2015	ICD estimated from Google Maps linework.
Oxon Hill, MD Prince George's Co. United States	Oxon Hill Rd. / (parking lots) (38.79166, -77.00416)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 26.0650	Other (At-Grade) Single-Lane	2015	ICD estimated from Google Maps linework.
Oxon Hill, MD Prince George's Co. United States	Oxen Hill Rd. / Cedar Ridge Dr. / Panorama Dr. (38.78452, -77.00597)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 34.4465	Other (At-Grade) Single-Lane	2015	ICD estimated from Google Maps linework.
Fort Washington, MD Prince George's Co. United States	Oxon Hill Rd. / Kerby Hill Rd. (38.77951, -77.00648)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 34.4490	Other (At-Grade) Single-Lane	2015	ICD estimated from Google Maps linework.
Jessup, MD Anne Arundel Co. United States	National Business Pkwy. / Brock Bridge Rd. (39.14025, -76.76395)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 44.4636	Other (At-Grade) Multilane (2 Lane, unspecified)	2013	ICD estimated from Google Maps linework.
Hanover, MD Anne Arundel Co. United States	Watts Ave. / Clark Rd. (39.15138, -76.72638)	Roundabout Existing	All-Way Yield None	2 Approaches 0 Driveways 25.9330	Other (At-Grade) Single-Lane	2008	ICD estimated from Google Maps linework.
Hanover, MD Anne Arundel Co. United States	Ridge Rd. / Corporate Center Dr. (39.19204, -76.70216)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 31.4719	Other (At-Grade) Single-Lane	2004	ICD estimated from Google Maps linework.
Catonsville, MD Baltimore Co. United States	UMBC Blvd. / Research Park Dr. (39.24874, -76.71580)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 44.3950	Other (At-Grade) Single-Lane	2015	Elliptical shape. ICD estimated from Google Maps linework.
Catonsville, MD Baltimore Co. United States	Hilltop Cir. / UMBC Blvd. (39.25178, -76.71442)	Rotary Existing	All-Way Yield None	4 Approaches 0 Driveways 60.1156	Other (At-Grade) Multilane (2 Lane, unspecified)	2015	Lane changes needed for some through movements. ICD estimated from Google Maps linework.
Bel Air, MD Harford Co. United States	Tollgate Rd. / Macphail Rd. (39.51959, -76.35208)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 19.8120	Other (At-Grade) Single-lane w/ Traversable Central Island	2012
Friendship, MD Anne Arundel Co. United States	Solomons Island Rd. (MD 2) / Friendship Rd. (MD 261) / Sansbury Rd. (38.73656, -76.59379)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 40.0594	Other (At-Grade) Single-Lane	2008	ICD estimated from Google Maps linework.
Laurel, MD Howard Co. United States	Old Scaggsville Rd. / High Ridge Rd. / Running Deer Dr. (39.11815, -76.86396)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 27.7985	Other (At-Grade) Single-Lane	2015	ICD estimated from Google Maps linework.
Columbia, MD Howard Co. United States	Harpers Farm Rd. / Campus Dr. (39.21534, -76.88023)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 31.4614	Other (At-Grade) Single-Lane	2003	Originally had 4 legs. ICD estimated from Google Maps linework.
Ellicott City, MD Howard Co. United States	College Ave. / Bending Sky Way (39.25754, -76.79122)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 26.8186	Other (At-Grade) Single-Lane	2012	ICD estimated from Google Maps linework.
Aberdeen, MD Harford Co. United States	Philadelphia Rd. (MD 7) / Ashford Dr.. / Panell Dr. (39.48593, -76.23873)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 41.4792	Other (At-Grade) Single-Lane	2012	ICD estimated from Google Maps linework.
Aberdeen, MD Harford Co. United States	Tralee Cir. / Ashford Dr. (39.48395, -76.23831)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 25.8100	Other (At-Grade) Single-Lane	2003	ICD estimated from Google Maps linework.
Aberdeen, MD Harford Co. United States	Burnt Hill Trl. / Atlas Cedar Way / Thistle Hill Dr. (39.49324, -76.22236)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 33.1799	Other (At-Grade) Single-Lane	2008	ICD estimated from Google Maps linework.
Aberdeen, MD Harford Co. United States	Burnt HIll Trl. / Witch Hazel Way / Limestone Ct. (39.49486, -76.22046)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 33.1791	Other (At-Grade) Single-Lane	2008	ICD estimated from Google Maps linework.
Aberdeen, MD Harford Co. United States	Thistle Hill Dr. / Witchhazel Way (39.49563, -76.22415)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 31.3355	Other (At-Grade) Single-Lane	2008	ICD estimated from Google Maps linework.
Aberdeen, MD Harford Co. United States	Burnt Hill Trl. / Holly Oak Cir. / Woods Line Dr. (39.49605, -76.21740)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 25.8055	Other (At-Grade) Single-Lane	2007	ICD estimated from Google Maps linework.
Konterra, MD Prince George's Co. United States	Bentley Park Dr. / Parkgate Dr. (39.09112, -76.91733)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 33.5280	Other (At-Grade) Single-Lane	2015
Perry Hall, MD Baltimore Co. United States	E Joppa Rd. / Scott Moore Way / Cowenton Ave. (39.40290, -76.44124)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 38.1000	Other (At-Grade) Single-Lane	2008	Right-turn bypass lane on west leg.
Hagerstown, MD Washington Co. United States	Hagers Crossing Dr. / Bartow Dr. / Sedgwick Way (39.65981, -77.75932)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 36.5760	Other (At-Grade) Single-Lane	2003	Year Completed estimated (1999-2005).
Robinwood, MD Washington Co. United States	Yale Dr. / Medical Campus Rd. / Caring Pathway Ln. (39.62594, -77.68707)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 36.5760	Other (At-Grade) Single-Lane	2016	Right-turn bypass lane on southwest leg.
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
Ballenger Creek, MD Frederick Co. United States	Jefferson Technology Pkwy. / Jefferson Station Blvd. (39.39223, -77.45291)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 42.6720	Other (At-Grade) Multilane (2 Lane, unspecified)	2014	Year Completed estimated (2013-2015).
Ballenger Creek, MD Frederick Co. United States	Holiday Dr. / Spectrum Dr. (39.38178, -77.40206)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 44.1960	Other (At-Grade) Multilane (2 Lane, unspecified)	2008	Left turn lane trap in circulatory roadway.
Bel Air North, MD Harford Co. United States	Red Pump Rd. / Yankee Doodle Dr. (39.54551, -76.37994)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 36.5760	Other (At-Grade) Single-Lane	2010
Bel Air South, MD Harford Co. United States	Woodsdale Rd. / Box Hill Corporate Center Dr. / (parking) (39.46498, -76.31016)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 30.4800	Other (At-Grade) Single-Lane	2014	Year Completed estimated (2013-2015).
Chester, MD Queen Anne's Co. United States	Castle Marina Rd. / Bayberry Dr. (38.98086, -76.28905)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 48.7680	Other (At-Grade) Single-Lane	2019	Year Completed estimated (2018-2019).
Severna Park, MD Anne Arundel Co. United States	East West Blvd. / Jumpers Hole Rd. / Adler Ct. (39.10765, -76.58306)	Roundabout Existing	All-Way Yield None	5 Approaches 0 Driveways 65.5320	Other (At-Grade) Single-Lane	1998	Elliptical shape. ICD 225 ft x 200 ft. Year Completed estimated (1994-2002).
Millersville, MD Anne Arundel Co. United States	Brightview Dr. / Galiot Dr. / Tremont Dr. (39.11196, -76.62028)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 30.4800	Other (At-Grade) Single-Lane	2008
Hanover, MD Anne Arundel Co. United States	Parkside Blvd. / Fredericksburg Rd. / Cornfield Ave. (39.13140, -76.75125)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 36.5760	Other (At-Grade) Single-Lane	2015
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).
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).
Severn, MD Anne Arundel Co. United States	Milestone Pkwy. / (unknown) (39.14341, -76.75076)	Roundabout Existing	All-Way Yield None	3 Approaches 0 Driveways 45.7200	Other (At-Grade) Multilane (2 Lane, unspecified)	2012	Year Completed estimated (2011-2014).
Severn, MD Anne Arundel Co. United States	Milestone Pkwy. / Clubhouse Dr. (39.14600, -76.74775)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 45.7200	Other (At-Grade) Multilane (2 Lane, unspecified)	2012	Year Completed estimated (2011-2014).
Severn, MD Anne Arundel Co. United States	Milestone Pkwy. / Split Creek Ln. / (parking) (39.15042, -76.74668)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 45.7200	Other (At-Grade) Multilane (2 Lane, unspecified)	2007
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).
Jessup, MD Anne Arundel Co. United States	Montevideo Rd. / Forest Ave. / Wigley Ave. (39.15966, -76.75916)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 33.5280	Other (At-Grade) Single-Lane	2007	Year Completed estimated (2006-2007).
Columbia, MD Howard Co. United States	Owen Brown Rd. / Martin Rd. (39.19989, -76.86930)	Roundabout Existing	All-Way Yield None	4 Approaches 0 Driveways 28.9560	Other (At-Grade) Single-Lane	2004	Year Completed estimated (2002-2005).