During 2020 it will be the 80th anniversary of the Pennsylvania Turnpike in the US. The 580km-long route runs from the border with Ohio State in the west to the border with Delaware State at the Delaware River
The turnpike forms part of the Interstate Highway System, although it does predate this. In various stretches it forms part of I-76, I-70, I-276 and I-95.
The Pennsylvania Turnpike was designed in the 1930s and utilised a number of tunnels that had originally been bored for a rail connection that was later abandoned. Site investigations showed that six of the nine rail tunnels could be used for the route. Two were bypassed by cuttings (one had been used for a rail line), while a third was in such a poor state of repair that an extra tube was driven in its place. Construction work started in October 1938, with the main highway featuring a concrete surface while asphalt paving was used for the on and off ramps.
The road opened to traffic officially on the 1st October 1940, predating the Interstate system by 16 years. After WWII, the original turnpike section was extended both to the east and west. The extension of its length was completed in 1956, in the same year as the Interstate construction programme commenced.
The route has been upgraded and improved many times since it opened to traffic.