The Canada Southern Railway (reporting mark CASO), also known as CSR, was a railway in southwestern Ontario, Canada, founded on February 28, 1868 as the Erie and Niagara Extension Railway.[1] Its name was changed to Canada Southern Railway on December 24, 1869.[2] The 1868 Act specified that it was to be constructed at a broad gauge of 5 ft 6 in (1,676 mm),[3] but that requirement was repealed in the 1869 Act,[4] thus allowing construction at the standard gauge of 4 ft 8+1⁄2 in (1,435 mm).
The railway was leased to the Michigan Central Railroad (MCR) for 99 years in 1883; in 1929 it was subleased to the New York Central Railroad (NYC). Its successors Penn Central (formed 1968) and Conrail (formed 1976) later exercised control before being sold to CN/CP in 1985.