Canal Creek Group Campground - Canal Creek Site

The Chesapeake and Ohio Canal, abbreviated as the C&O Canal and occasionally called the Grand Old Ditch, operated from 1831 until 1924 along the Potomac River between Washington, D.C., and Cumberland, Maryland. It replaced the Patowmack Canal, which shut down completely in 1828, and could operate during months in which the water level was too low for the former canal. The canal's principal cargo was coal from the Allegheny Mountains.

Construction began in 1828 on the 184.5-mile (296.9 km) canal and ended in 1850 with the completion of a 50-mile (80 km) stretch to Cumberland, although the Baltimore and Ohio Railroad had already reached Cumberland in 1842. The canal had an elevation change of 605 feet (184 meters) which required 74 canal locks, 11 aqueducts to cross major streams, more than 240 culverts to cross smaller streams, and the 3,118 ft (950 m) Paw Paw Tunnel. A planned section to the Ohio River in Pittsburgh was never built.

The canal is now maintained as the Chesapeake and Ohio Canal National Historical Park, with a trail that follows the old towpath.