Trivia Tuesday, July 7
Last week's answer
Question:
When the Pennsylvania Turnpike opened in 1940, it revolutionized American highway design with its divided lanes, gentle curves and lack of steep mountain grades. To slice straight through the rugged Appalachian Mountains without forcing cars up punishing slopes, engineers saved years of blasting and excavation work by utilizing what existing infrastructure?
Answer: A network of half-carved, abandoned 1880s railroad tunnels left behind by a bankrupt trans-Pennsylvania rail project that was never completed.
Seven of the Pennsylvania Turnpike's tunnels were originally excavated for the unfinished South Pennsylvania Railroad. The PA Turnpike later built the Lehigh Tunnel. As traffic volumes increased and the railroad tunnels grew older, some of the original railroad tunnels were bypassed or abandoned. The PA Turnpike operates five tunnels today.
Sources: PA Turnpike