March 18, 1834
The first railway tunnel in the United States made its formal debut in west-central Pennsylvania as part of the infrastructure for the Allegheny Portage Railroad. The Staple Bend Tunnel was specifically built between the borough of Conemaugh (the present-day city of Johnstown) and the settlement (now borough) of Hollidaysburg. At the time of its opening, this tunnel was only the third of its kind in the world.
Construction on the Staple Bend Tunnel had begun in 1831 and was supervised by a chief engineer named Sylvester Welch. Those who worked on this ambitious project included numerous Welsh miners and Irish laborers. They steadily chipped away at and blasted apart 901 feet (275 meters) of solid rock to create the tunnel. About 14,900 cubic yards (11,400 cubic meters) of bedrock were ultimately removed.
When it was completed, the Staple Bend Tunnel measured 25 feet (7.6 meters) in width and 21 feet (6.4 meters) in height. This tunnel quickly proved to be a vital link in a rail system that transported canal boats and other cargo over the Allegheny Mountains.
Photo Credit: National Park Service
For more information on the Staple Bend Tunnel, please check out https://en.wikipedia.org/wiki/Staple_Bend_Tunnel and https://www.nps.gov/alpo/learn/historyculture/staplebend.htm