In October 1988 the Pennsylvania Turnpike Commission celebrated the fiftieth anniversary of the beginning of construction on Pennsylvania's first super-highway. October 1990 will mark the similar anniversary of the turnpike 's official opening to traffic. Probably few of those who travel the turnpike today are aware that the route was originally planned as a railroad and that after two years of construction in the 1880's, the project lay abandoned for fifty-three years before the Turnpike Commission revived it.
Passageways evolve out of topography and out of the general location of the area with reference to destinations. For about seventy miles the Cumberland Valley of Pennsylvania extends southwestward from the Susquehanna River across from Harrisburg to the Potomac River in Maryland. The Valley is bounded in the southeast by South Mountain and on the northwest by Blue Mountain. The eastern two-thirds of the Valley is drained eastward by the widely meandering Conodoguinet Creek, which from Roxbury Gap traverses the northern side of the Valley for a distance of about 100 miles in an air distance of forty-three miles.