The Whitehall and Plattsburgh Railroad was a railway company that built but did not operate two disconnected railway lines in Upstate New York in the 19th century. Its purpose, to build a 90-mile (140 km) railway line between Whitehall, New York, and Plattsburgh, New York, was realized by its successor, the New York and Canada Railroad, albeit over a different route between Port Henry, New York, and Plattsburgh. Its northern line, between Plattsburgh and Ausable, New York, became the Ausable Branch of the Delaware and Hudson Railway and was abandoned in 1981. Its southern line, between Port Henry and Ticonderoga, New York, was incorporated into the New York and Canada Railroad main line and today is part of the Canadian Pacific Kansas City's Canadian Subdivision.