I thought it might be good to give some background on the Pennsylvania Railroad's Chautauqua Branch. The branch ran from Oil City, PA to Buffalo, NY:

Towns in Pennsylvania;

Oil City

Titusville

Spartansburg

Corry

Towns in New York;

Clymer

Sherman

Mayville

    At Brocton, NY the Chautauqua Branch joined the Nickle Plate Road mainline to Buffalo, NY creating a double track line from Brocton to Buffalo. The PRR owned the east bound main track and the NKP owned the west bound main track.