It operated a 34-mile long (55 km) main line between Columbia, Pennsylvania, and Port Deposit, Maryland, generally along the eastern shore of the Susquehanna River.

The C&PD was subsequently purchased by the Pennsylvania Railroad (PRR) and, since the 1999 breakup of Conrail, is owned by Norfolk Southern Railway.

[1][2] The C&PD began construction in 1866, as another rail line, a branch built by the Philadelphia, Wilmington and Baltimore Railroad (PW&B), approached Port Deposit from the southeast.

The first completed section of the C&PD opened in 1868 and connected the newly built Philadelphia and Baltimore Central Railroad at Rowlandsville (4 mi (6.4 km) north of Port Deposit) to the PW&B branch line.

Scheduled passenger service over the Port Road ended on October 29, 1978, when Amtrak re-routed the National Limited's Washington section via Philadelphia.