In May 1976 , the Gazette International reported the opening of the Washington metro railway .
Washington metro opens Railway Gazette International May 1976 page 163 Arlington County , Virginia was linked to the system on July 1 , 1977 ; Montgomery County , Maryland , on February 6 , 1978 ; Prince George 's County , Maryland , on November 17 , 1978 ; and Fairfax County , Virginia , and Alexandria , Virginia , on December 17 , 1983 .
Washington Metro