Service on the Green Line tracks began on May 11, 1991 on three stations between U Street/African-American Civil War Memorial/Cardozo and Gallery Place-Chinatown.
Internally, the Green Line is known as the Greenbelt Route (E) and the Branch Avenue Route (F), which meet at the center of the lower level platform of Gallery Place-Chinatown station (whose Remote Terminal Unit (RTU) code is F01, the first station on the Branch Avenue Route) [REF].