Lehigh Tunnel
The Lehigh Tunnel is a pair of road tunnels that carries the Pennsylvania Turnpike Northeast Extension under Blue Mountain north from U.S. Route 22 in the Lehigh Valley to the Scranton/Wilkes-Barre area between mileposts 70.7 to 71.5.
Description
Construction on this tunnel began on September 21, 1955. Originally a single tunnel that opened to traffic on April 1, 1957, turnpike officials changed the name from the originally-planned "T. J. Evans Tunnel" to the "Lehigh Tunnel" after Evans, chair of the turnpike commission during the time the tunnel was planned, was accused of defrauding the government. The new name also helped to differentiate the Lehigh Tunnel from the existing Blue Mountain Tunnel on the mainline.The tunnel was twinned in 1991 to allow two lanes of traffic in each direction. It has an unusual appearance, as the original tunnel is rectangular, as it used the older dig-and-blast technique, while the new tube is oval, having been constructed using the New Austrian tunnelling method.
From 1980 to 1996, the Northeast Extension was designated as Pennsylvania Route 9, as opposing traffic faced each other in the single tube prior to the opening of the current southbound tube, and therefore did not qualify for Interstate highway status, which was granted five years after the completion of the southbound tube.
The Lehigh Tunnel crosses the border between Lehigh County and Carbon County. It is the only road tunnel crossed by the Appalachian Trail.