The Beltway Series, promoted by the teams as "The Battle of the Beltways," is the Major League Baseball (MLB) interleague rivalry series played between the Baltimore Orioles and Washington Nationals. The Orioles are a member of the American League (AL) East division, and the Nationals are a member of the National League (NL) East division. The series name is taken from the beltway highways, the Baltimore Beltway (I-695) and the Capital Beltway (I-495), that serve Baltimore, Maryland, and Washington, D.C., respectively.