Tuesday, September 18, 2012

"Tunnel Vision"

In spite of the Turnpike Commission dubbing the new road "The World's Greatest Highway", the Turnpike was popularly known as the "Tunnel Highway". Many souvenirs promoted the original stretch's seven tunnels through Pennsylvania's Appalachian Mountains. These tunnels, from east to west, bored through Blue Mountain, Kittatinny Mountain, Tuscarora Mountain, Sideling Hill, Ray's Hill, Allegheny Mountain, and Laurel Hill.

Above: The Bankhead Tunnel runs underneath the Mobile River in Alabama. The tunnel was built in sections and floated to the proper positions, then sunk. Each section was sunk next to the previous section and joined underwater. Only passenger cars and pickup trucks are still allowed to travel through the tunnel, as it is very narrow.

Construction of the Liberty Tunnels began in 1919. The boring of the 5889 foot tubes was completed in 1922. When the Liberty Tunnels were opened to traffic in 1924, they were considered an engineering marvel. The nearly two-mile span was the longest tunnel in the country at that time.