MTA Commuter Bus 201 operates between the Gaithersburg Park and Ride lot located at I-270 and MD 124 in Montgomery County and BWI Marshall Airport. The 201 makes stops at the Shady Grove Metro, the Georgia Avenue Park & Ride, the Burtonsville Park & Ride, and Arundel Mills Mall. At BWI Marshall, the 201 stops at Concourses A (Southwest Airlines) and E (International terminal), dropping off passengers on the upper level and picking up passengers on the lower level. The route terminates at the BWI Rail Station. Buses depart BWI Marshall Airport hourly on weekdays from 5:05 a.m. to 11:05 p.m. and on weekends/holidays from 9:05 a.m. to 11:05 p.m.
For fares and additional information visit the MTA website.