The Pennsylvania Turnpike, America''s first Superhighway, turned 60 years old on October 1,2000.

   When the first stretch opened to traffic in 1940, it ran from Middlesex near Harrisburg to Irwin near Pittsburgh. It was America''s first limited access, four-lane, divided highway-no stoplights,stop signs or cross traffic. It cut three hours off the trip from Harrisburg to Pittsburgh.
   The $70 million,160-mile Turnpike offered long straight-aways, relatively gentle curves and easy grades.Its original Portland cement concrete (PCC) pavement consisted of two 12-foot traffic lanes in each direction. It is this stretch of 9-inch-thick PCC--all of it overlaid with asphalt--that is being totally reconstructed by the Pennsylvania Turnpike Commission.

Early pavement problems
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