PENNSYLVANIA TURNPIKE

First modern super-highway

In the 1930's, the paved highway was taken to the next - and present - level with the decision to build the Pennsylvania Turnpike. This was to be a limited access, super-highway, with no stop signs, traffic lights, or cross-traffic. The first in the nation, and a prototype for the modern highways and interstate system of today.

Legislation passed for its construction in May of 1937, and actual construction began on Oct. 27, 1938. In less than two years - Oct. 1, 1940 - it opened to traffic. The original segment was 160 miles long, stretching from Carlisle (near Harrisburg) to Irwin (near Pittsburgh). Other segments have been built so that today the total length is 506 miles.

But the story actually begins in the 1880's, when a battle was going on between the Pennsylvania Railroad and the New York Central Railroad. The New York Central's chairman, Colonel William H. Vanderbilt, wanted to build a route that would tie his railroad with the steel mills in Pittsburgh, and bypass the Pennsylvania Railroad's lines. To help in this effort, he enlisted the support of several Pittsburgh industrialists such as Andrew Carnegie to form the South Pennsylvania Railroad. They had spent nearly ten million dollars when financial speculator J. P. Morgan arranged a truce between Vanderbilt and the Pennsylvania RR. However, much grading had been done, as well as work on digging tunnels through the mountains.

It was the right-of-way and tunnels that state officials in the 1930's began envisioning as a toll highway, replacing the hilly and windy routes over the mountains of central Pennsylvania. They also thought money might be available from the Federal government as a work-relief project. This project not only put thousands of people to work during the depression years, but was also a way of getting war supplies to the eastern shipyards faster from Pittsburgh and the mid-west.

Engineering for the highway was a great challenge. They were expected to use design specifications and safety standards that had never been used in this country. They had to design easy grades, all-weather access, long sweeping curves, and safe entrances and exits, and all of this over some very mountainous terrain. To do this, they planned; four wide lanes (except through the tunnels); a maximum grade of 3 percent (compared to 9 percent on existing roads); a maximum curve of 6 degrees with banking to help cars and trucks keep their traction; limited access entrance and exit ramps, each 1,200 feet long.

Today the Turnpike, including extensions, is 506 miles long, has 49 interchanges, 22 service plazas, and has served as the example for the building of the modern super-highways and the Interstate Highway system.