One of my favorite vacations involves the 4 tunnels of this parkway. My two younger brothers and I with our Dad drove from Indiana to Camden New Jersey where Dad's old Battleship the USS New Jersey is now docked as a floating museum. That will always be a cherished vacation because it was the last trip Dad took before failing health took his life.
Thank you for posting the pictures on here.
This tunnel was not built for the railroad. The original tunnel is about 80 feet to the south but was deemed unusable, an entirely new one was built.
These turnpike tunnels were actually built for the railroads and then abandoned. Pennsylvania bought them when they were constructing their turnpike.