Southern Avenue is an island platformed Washington Metro station in Hillcrest Heights, Maryland, United States. The station was opened on January 13, 2001, and is operated by the Washington Metropolitan Area Transit Authority (WMATA). Providing service for only the Green Line, the station is located on the southern side of Southern Avenue, putting it just outside the District of Columbia, opposite Valley Terrace. Southern Avenue is the first station in Maryland going southeast on the Green Line.