The Pennsylvania Turnpike, often considered the first superhighway in the United States, opens to traffic.
The Pennsylvania Turnpike (Penna Turnpike or PA Turnpike) is a toll highway operated by the Pennsylvania Turnpike Commission (PTC) in the U.S. state of Pennsylvania. A controlled-access highway, it runs for 360 miles (580 km) across the state. The turnpike's western terminus is at the Ohio state line in Lawrence County, where the road continues west as the Ohio Turnpike. The eastern terminus is at the New Jersey state line at the Delaware River–Turnpike Toll Bridge over the Delaware River in Bucks County, where the road continues east as the Pearl Harbor Memorial Extension of the New Jersey Turnpike.
The highway runs east–west through the southern part of the state, connecting the Pittsburgh, Harrisburg, and Philadelphia areas. It crosses the Appalachian Mountains in central Pennsylvania, passing through four tunnels. The turnpike is part of the Interstate Highway System; it is designated as part of Interstate 76 (I-76) between the Ohio state line and Valley Forge, I-70 (concurrent with I-76) between New Stanton and Breezewood, I-276 between Valley Forge and Bristol Township, and I-95 from Bristol Township to the New Jersey state line. The road uses an all-electronic tolling system; tolls can be paid using E-ZPass or toll-by-plate (which uses automatic license plate recognition). Historically, cash tolls were collected using a combination of the ticket system and a barrier toll system, but cash tolls were phased out between 2016 and 2020. Along the turnpike are 15 service plazas, providing food and fuel to travelers.
During the 1930s the Pennsylvania Turnpike was designed to improve automobile transportation across the mountains of Pennsylvania, using seven tunnels built for the abandoned South Pennsylvania Railroad in the 1880s. The road opened on October 1, 1940, between Irwin and Carlisle. It was one of the earlier long-distance limited-access highways in the United States, and served as a precedent for additional limited-access toll roads and the Interstate Highway System.
Following World War II, the turnpike was extended east to Valley Forge in 1950 and west to the Ohio state line in 1951. In 1954, the road was extended further east to the Delaware River, and construction began on the Northeast Extension of the turnpike. The mainline turnpike was finished in 1956 with the completion of the Delaware River Bridge. During the 1960s, an additional tube was bored at four of the two-lane tunnels, while the other three tunnels were bypassed; these improvements made the entire length of the mainline turnpike four lanes wide. Improvements continue to be made to the road: rebuilding the original section to modern standards, widening portions of the turnpike to six lanes, and adding interchanges. In 2018, an ongoing interchange project saw the redesignation of the easternmost three miles (4.8 km) of the road from I-276 to I-95. Though still considered part of the turnpike mainline, it is no longer signed with turnpike markers and uses I-95's mileposts and exit numbers.