The "C" Branch, also called the Beacon Street Line or Cleveland Circle Line, is one of four branches of the Massachusetts Bay Transportation Authority's Green Line light rail system in the Boston, Massachusetts metropolitan area. The line begins at Cleveland Circle in Brighton and runs on the surface through Brookline along the median of Beacon Street. Entering Boston, the line goes underground through the St. Marys Street Incline and joins the "B" and "D" Branches at Kenmore. Trains run through the Boylston Street Subway to Copley where the "E" Branch joins, then continue through the Tremont Street Subway to downtown Boston. As of 2013, the "C" Branch terminates at North Station; further service to Lechmere is provided by the "E" Branch.