Montgomery County is located just North of Washington D.C. Rockville, Bethesda, Gaithersburg and Potomac are widely known and popular cities within M.C.. Attractions include The National Capital Trolley Museum, the Clara Barton House, and the National Museum of Health and Medicine. With unparalleled access to major commuter routes into Washington D.C. Montgomery County has long been held as a major metropolitan commuter area for those working in the District, NIH and/or the Maryland I-270 Bio Corridor who call Montgomery County their home.