Ever wondered how race cars are tested? Generally, they are tested in a wind tunnel with a static car (as it is too difficult to test them in the real world). But one long-abandoned old 1800s railway tunnel in Pennsylvania provided the ideal environment to test the high-tech race cars that sit on the cutting edge of technology in real life.

For years this tunnel, called the Laurel Hill Tunnel, was treated as top secret - not the Air Force's Area 51 level top secret - but a secret that soon caught the eye of hikers in the region. There are many secret and abandoned tunnels all around the world - and mostly under the cities - like Chicago's sealed-up freight tunnels.

A Relic of The Never Completed South Pennsylvania Railroad

A series of tunnels had been built for the South Pennsylvania Railroad in the 19th century but the project was eventually abandoned. Later in the Great Depression, these tunnels were incorporated into a new Turnpike project in an effort to build a superhighway across Pennsylvania.

  • Pennsylvania Turnpike: Became Known As "America’s first superhighway"
  • Open: The Pennsylvania Turnpike Opened in 1940
  • The Tunnels: Built For a Never Completed Railroad in The 1880s and 1890s

While the turnpike proved an instant success, by the 1960s its tunnels were becoming bottlenecks and were possibly even dangerous to motorists.

The turnpike's original route was opened during World War Two in October 1940 and used six of the railroad's nine tunnels. Some of the original train tunnels were not used due to structural concerns or being bypassed due to engineering advances since the 1880s. Still, others were later bypassed through re-alignments and subsequently abandoned.

The Laurel Hill Tunnel is a 4,541-foot-long (1,384 m) tunnel on the Pennsylvania Turnpike. But it was bypassed and abandoned in 1964 and remained largely unused until 2003. And thus Laurel Hill Tunnel lay abandoned for years. During this time it was sporadically for storage and even as a firing range.

  • Where To See: The Western Portal Can Be Seen From The Eastbound Side of The Turnpike - Milepost 99.3
  • Length: 4,541 Feet (1,384 meters)
  • Abandoned: 1964

Today one can now see the relics of the "ghost railroad" all across the Alleghenies.

Other Abandoned Tunnels:

  • Allegheny Mountain Tunnel
  • Quemahoning Tunnel
  • Negro Mountain Tunnel
  • Memorial Tunnel

Related: These Roman Tunnels Were Once The Longest Of The Ancient World

A Top Secret New Race Testing Life

But then re-construction of the site began in 2003 and rumors about its use started circulating the next year. Some of the stories came from hikers in the area that shed more light on what was going on there. They would report hearing screaming burnouts and deep-tone V8s blasting through their gears.

Unlike the other tunnels (like the Sideling Hill and Rays Hill tunnels) the Laurel Hill Tunnel is not open to the public and it is reported to be routinely patrolled by the police for trespassers.

Today it is now known that the abandoned highway tunnel is being used by Chip Ganassi Racing for high-speed race car aerodynamic testing.

The tunnel has been repaved, equipped with climate control, safety equipment, and data collection systems. The tunnel was even used to develop the G-Force Indycar in 2004.

"Rumours of an abandoned highway tunnel being used by a racing team were the talk of the industry, but details were sketchy at best. Eventually Racecar Engineering managed to get hold of images of the tunnel in use which showed some intriguing modifications, including a large metal structure that has been added to the eastern end of the tunnel."

- Racecar Engineering

Racecar Engineering concludes that what has been built is a coastdown tunnel. That is a "tool that combines the best elements of real world, straight-line testing and conventional wind tunnels."

Related: Are There Really Tunnels Under New York City? This Is What We Know

Advantages of Using The Laurel Hill Tunnel

The advantage of the tunnel is that they can do limitless straight-line testing in perfect conditions devoid of wind but with controlled temperatures. Plus they can do this with a full-scale and real car.

  • Wind: No Wind or Cross Winds
  • Climate: Climate Controlled

The tunnel needed a lot of work to get into a usable condition. When the racing team found it in 2003 it was half full of road-making material and a complete mess.

The tunnel has allowed the racing team to turn new designs around quickly. The tunnel is working the opposite way of conventional wind tunnels where the air is forced around a static car.

With this controlled stretch of tunnel, they can do all the tests and measurements in a much more real-life setting. They can even control the environment in the tunnel heating and cooling the temperatures as desired - plus there are no worries about crosswinds. Climate control means the tunnel is effectively sealed.

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