Anyone who has taken a trip west from the midstate on the Pennsylvania Turnpike past Carlisle toward Pittsburgh knows the trip involves driving through tunnels.
If you first made the trip more than 45 years ago, you may have noticed something missing: three of those tunnels. Today, the trip includes tunnels at Allegheny Mountain, Tuscarora Mountain, Kittatinny Mountain and Blue Mountain. (There's another more recent tunnel on the Northeast Extension.) When the turnpike opened in 1940, it also included Ray's Hill, Sideling Hill and Laurel Hill tunnels.
I am sure as the tunnels started disappearing from the route in the 1960s (Laurel Hill in 1964, the other two in 1968), drivers must have wondered where those other tunnels went. Well, it turns out they didn't go anywhere. The tunnels are right where they have always been; it's the highway that moved.
To understand the tunnels, you must examine the turnpike's history. When planning for the Pennsylvania Turnpike began, engineers started with a route that had been planned decades earlier. Nineteenth century industrialists Andrew Carnegie and Henry Frick tired of the Pennsylvania Railroad monopoly and teamed up with William Vanderbilt, owner of the New York Central railroad, to build the South Pennsylvania Railroad. They had the route surveyed and construction got under way from 1881 to 1885. To finish the route, workers had to do significant grading work and bore nine tunnels through the mountains.
The railroad was never completed, and eventually the route, or its "right-of-way" was sold to the Turnpike Commission. Turnpike builders (reportedly including two veterans of the 1880s project) used six of the nine unfinished tunnels. A completely new tunnel was created for Allegheny Mountain, while engineers opted not to use the two others.
When the turnpike opened, it was called the nation's "First Superhighway" with limited access and two lanes of traffic in either direction. The lanes merged at each tunnel, where vehicles passed each other with one lane in each direction. The slowdown at each tunnel led to a plan to bore parallel tunnels, which all the tunnels in use today have. Three tunnels did not get the parallel treatment.
By 1964, construction was completed on a cut through the terrain that bypassed the Laurel Hill tunnel in Somerset County. It's visible from the eastbound lanes at mile marker 99.2. This tunnel is still owned by the Turnpike Commission and is leased to a private company. It is not accessible to the public.
In Bedford and Fulton counties, the Turnpike Commission decided it was more economical to reroute the highway around the Sideling Hill and Ray's Hill tunnels instead of boring new ones. A new Sideling Hill rest stop was created as the new 13-mile route bypassed the old Cove Valley Service Plaza.
Today as you drive on the turnpike near Sideling Hill, you can see a large paved area where truckers often pull over to rest along the eastbound lanes. This is where the old section of the turnpike begins. It ends 13 miles to the west near Breezewood.
This abandoned section of the turnpike was used for a variety of purposes through the years. Designers tested the reflectivity of road signs by running tests in which subjects were driven through the old tunnels and report how well the signs reflected from the vehicles' headlights. Road cuts, now found along many highways and local roads to warn drivers who drift from their lanes, were tested on the abandoned roadway. Finally, some military units trained on the abandoned roadway prior to assignments in the Middle East within the past 15 years.
The abandoned section of the turnpike is now maintained by Pike 2 Bike and open to bicycles and hikers. While many people have suggested plans to create a museum of turnpike history, to re-light the tunnels and other improvements, none have materialized yet.
You can find the abandoned turnpike by going to the intersection of U.S. Route 30 and Pump Station Road near Breezewood. From the intersection, you will be able to see a small hill. Over the hill lies the old roadway.
If you venture in the tunnels, you will need a flashlight and a backup. Sideling Hill was the longest of all turnpike tunnels, and you cannot see light at either end when you are in the middle.