South Pennsylvania Railroad - Pennsylvania Turnpike

Pennsylvania Turnpike

The route was revived during the Great Depression, when plans were made to build a superhighway across Pennsylvania. In 1937 the new Pennsylvania Turnpike Commission bought the old line from the two railroads, and in 1938 construction began between Carlisle and Irwin. Two of the workers from the South Penn project (one contractor and one laborer) also worked on the Turnpike despite the 54-year time difference in construction.

The turnpike's original route was opened in October 1940, using six of the South Penn's nine tunnels (subsequent route re-alignments have caused some of these tunnels to be abandoned), while the original Allegheny Mountain Tunnel wasn't used due to structural concerns and the Quemahoning Tunnel and Negro Mountain Tunnel were bypassed because advances in engineering since the 1880s allowed for bypasses. The highway engineers did not use most of the railroad's other grading, however, since they could afford steeper grades and shorter alignments. Because of this, relics of the "ghost railroad" may still be found all across the Alleghenies.