There are ghost highways all around the country. These include highway tunnels and whole multilane segments of highways that have been bypassed. Today one can go sleuthing and discover these decaying pieces of infrastructure - sometimes they are overgrown or degraded to the point that they look post-apocalyptic.

Some like the abandoned tunnels of the Turnpike in Pennsylvania have even been used as stage sets in post-apocalyptic movies like the 2009 movie The Road. Many of these highways are no longer found on maps and many are sealed off. But there are many more that one can discover.

The Abandoned Pennsylvania Turnpike
Perhaps the best-known example of a ghost highway in the United States is the 13 mile-long stretch of the Abandoned Pennsylvania Turnpike. This section of road has two 2-lane tunnels (Ray's Hill Tunnel and the Sidelining Hill Tunnel) and 4-lane approaches were bypassed with 4-lane cuts at its core.

Today these two old tunnels and their approaches are being rehabilitated as part of a multi-use trail (mostly for cycling).

There are more abandoned tunnels along other sections as well as other abandoned and never used tunnels from the never completed South Pennsylvania Railroad that was partly constructed in the 1880s.

Abandoned tunnels Of The Turnpike and The South Pennsylvania Railroad include:

Negro Mountain Tunnel: Built For The South Pennsylvania Railroad But Bypassed By The Turnpike

Quemahoning Tunnel: Built For The South Pennsylvania Railroad But Bypassed By The Turnpike

Memorial Tunnel: Two-lane Vehicular Tunnel Built For The Turnpike, Later Abandoned

Laurel Hill Tunnel: Repurposed for High-Speed Racecar Aerodynamic Testing

Rays Hill Tunnel: Abandoned In 1968, One of the Three Original Pennsylvania Turnpike Tunnels To Be Abandoned

Sideling Hill Tunnel: Abandoned In 1968, One of the Three Original Pennsylvania Turnpike Tunnels To Be Abandoned

Intriguingly, the old Laurel Hill Tunnel was redeveloped in 2003 has been repurposed for high-speed racecar aerodynamic testing (and is off-limits).

U.S. Route 66 - Undermined By Mining
U.S. Route 66 had a number of realignments resulting in a number of sections being bypassed, decommissioned, and abandoned. Eventually, the whole route itself was decommissioned as a highway in 1985 (although most of its sections remain in use).

US Route 66: Decommissioned As A Highway In 1985

Since then parts of the old road have been redesignated as a National Scenic Byway called "Historic Route 66". There are many museums and nostalgic hotels, pubs, and restaurants along the old Route 66, one can learn a lot about the history of this famous old American highway.

Over its years, the route was constantly realigned and modified so in many cases there isn't just one route. One example of a ghost section of Route 66 is a one-mile section of the highway that buckled and broke. In response, the route was re-routed along a detour (55th St. and East Ave.) according to WRKR.com.

Location: Chicago Suburb of McCook

Name: Called Joliet Road

Access: Closed Off - Not Even Pedestrian Traffic Is Allowed

Today this section of Route 66 is completely closed and gated off. The highway was ruined by large quarries on either side of the road operated by Vulcan Materials Co. (the second-largest mining company and producer of aggregate in the world). The quarrying made the venerable highway too unstable to support traffic by undermining the road's bedrock foundations.

Highways That Were Never Completed & Ghost Highways
There are many examples of roads and railroads that were never fully completed and it is impossible to list any amount of them out here.

Located just east of Lancaster the Pennsylvania Route 23 "Goat Path" was graded for a four-lane expressway. But after much of the road had been built it was canceled. In the end, the roadbeds were planted over with grass.

R.H. Thomson Expressway is located in Seattle - it was never finished and the work ended leaving stub ramps. More unused ramps are to be seen for the never-built Inner Belt and Southwest Corridor in Boston, Massachusetts. They are part of an unused alignment for I-95.

In Connecticut, one will find the state's only four-level stack interchange along the I-84, near Hartford - but only part of it is used. One can see more stubs in New York in their parkway system, examples include exit 2 and exit 9 on the Cross County Parkway, the Taconic State Parkway at I-90, and the Northern State Parkway at NY 454.

Other Examples Of Ghost Highways In The United States:

Route 61: Near Centralia, Pennsylvania

Carciquez Drive: In California

Old US Highway 50: West of Washington, Indiana

Schuylkill Parkway: In Pennsylvania Near Bridgeport

With a bit of exploration one is likely to find ghost highways, railroads, tunnels, and roads near wherever one lives. They are something one can find in one's backyard.