The Turn Hole Tunnel: Constructed in 1866 by the Lehigh and Susquehanna Railroad, this tunnel eventually became part of the CNJ and carried the line's two track main into Jim Thorpe, PA. It was deemed unsafe in 1910 but remained in use into the 50's as a passing siding. Currently, the tunnel is open to the public and is one of Lehigh Gorge State Park's attractions. The bridge to the right is the new alignment which parallels the Lehigh line and now serves as a motorway into the park. Interior view here.