Paw Paw Tunnel

The Paw Paw Tunnel is a 3118 ft. (950.37 m.) long canal tunnel on the Chesapeake and Ohio Canal, near the border of Maryland and West Virginia, adjacent to the Potomac River. Though surpassed by many tunnels today, it remains one of the world's longest canal tunnels and was one of the greatest engineering feats of its day.

The tunnel was initially expected to cut six miles off the canal route and take two years to complete when planned out in 1836. Construction ended up taking fourteen years, plagued by enormous cost overruns, disease outbreaks, and ethnic violence between the workers. Construction proceeded at only 12 feet per week until completion in 1850.

The name of the tunnel comes from the abundance of Pawpaw (a.k.a. Paw Paw) trees in its vicinity.