Forty year ago, the Eisenhower Tunnel — the highest vehicle tunnel in the world, at 11,155 feet — opened in Colorado.
The tunnel, dug directly through the Continental Divide, eliminated the 9.5-mile drive over Loveland Pass.
Eisenhower tunnel facts
• Cost: $116.9 million westbound; $144.9 million eastbound. (In today’s dollars, the cost to build one bore would be $1 to $1.5 billion).
• Travel width: 26 feet (two 13 foot lanes) each direction.
• Ventilation fans: 16 westbound, 12 eastbound. Each fan is 10 feet, 6 inches in diameter.
• Highest 24 hour traffic count: 50,918 on Aug. 2, 2009.
• Highest 1 hour traffic count: 4,708 on March 9, 2007.
(Source: The Denver Post)