Willow is a station on the Overbrook branch of the Port Authority of Allegheny County's light rail network. It is located in Castle Shannon, Pennsylvania. It is a transfer point between the Beechview (serving Castle Shannon, Mt. Lebanon, Dormont, and Beechview) and Overbrook (serving Overbrook, Carrick, Bon Air, and Belzhoover) lines. The station's name was derived from Willow Ave, the street that runs parallel with and across the light rail.