Parking throughout the District of Columbia is restricted generally (see individual area signs for site specific closures/restrictions) from 12:00 A.M. to 6:00 A.M. to facilitate cleaning and maintenance.
Washington, D.C. is a very busy metropolitan area. Parking is at a premium throughout the entire city. Private paid parking garages and lots can be found downtown north of the National Mall. Free on street parking is generally restricted to two hours (ticketing/towing enforced). Limited free day long parking is available along Ohio Drive, SW which is along the Potomac River south of the Lincoln Memorial or in Lots A, B & C south of the Thomas Jefferson Memorial.
Information and schedules for Metro can be found at www.wmata.com.