Conceived and built during the Great Depression, The Pennsylvania Turnpike is the Grandfather of the Interstate Highway System. The original roadway was a scant 160 miles long, running from Irwin, just east of Pittsburgh to Middlesex, just west of Harrisburg, Pa. This 160 mile piece of roadway, however, revolutionized automobile travel in the United States. The Pennsylvania Turnpike was the first roadway in the United States that had no cross streets, no railroad crossings, and no traffic lights over its entire length. A trip through the mountains of Pennsylvania with grades of no more than 3 was unheard of prior to this time. A fourlane superhighway through the Allegheny Mountains with unrestricted passing except through tunnels, the Pennsylvania Turnpike even made the pages of Scientific American due to its stateoftheart design and construction. One of the hallmarks of the original turnpike were the seven tunnels bored through the mountains of Pennsylvania. A trip on the turnpike with its seven tunnels was an exciting part of many family vacations in the days when only a handful of superhighways existed. Now that we have a nationwide system of the tollfree Interstate Highways it is difficult to imagine how special a trip on the turnpike was back then.

Website: http://users.zoominternet.net/~jamieo/Turnpike_Page.htm