Railway Tunnel
This rail tunnel through the Berkshires, completed in 1875, connected eastern Massachusetts to the industrial and transportation centers in upstate New York and the Great Lakes. At the time of completion it was the longest tunnel in the world, at 4.75 miles, and nearly 200 lives were lost during...
A 6.2-mile railway tunnel through the Continental Divide in the Rocky Mountains, completed in 1928. The longest main-line railway tunnel in the USA.
This tunnel under San Francisco Bay carries commuters on the subway between Oakland and San Francisco, and is one of the longest immersed tunnels in the world. Immersed tunnels are constructed using pre-made tubes that are floated to the location and sunk into place. The segments are then attached...