WASHINGTON, D.C. - APRIL 10, 2015: Trains and passengers in a Metro Station. Opened in 1976, the Washington Metro is now the second-busiest rapid transit system in the U.S.
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WASHINGTON, D.C. - APRIL 10, 2015: Trains and passengers in a Metro Station. Opened in 1976, the Washington Metro is now the second-busiest rapid transit system in the U.S.