Eisenhower–Johnson Memorial Tunnel

Clear Creek County Colorado

“We were going by the book but the mountain couldn’t read” said one engineer during the long costly construction of this four-lane vehicular tunnel (for cars and trucks) through the Rocky Mountains. When engineers hit upon shifting fault lines emergency measures had to be taken to stop the tunnel from caving in. Though the project was supposed to take three years it actually took five. It was completed in 1979.

At 11158 feet the Eisenhower Tunnel is one of the highest in the world. At 1.7 miles (2.7 kilometers) it’s also the longest mountain tunnel in the US Interstate system. It cuts under the Continental Divide the point at which bodies of water that drain into the Pacific are divided from the bodies of water that drain into the Atlantic.