Eisenhower Tunnel
tunnel in Colorado
The Eisenhower Tunnel, officially the Eisenhower–Edwin C. Johnson Memorial Tunnel, is a dual-bore, four-lane vehicular tunnel in the western United States, approximately 60 miles (97 km) west of Denver, Colorado. The tunnel carries Interstate 70 (I-70) under the Continental Divide in the Rocky Mountains. With a maximum elevation of 11,158 feet (3,401 m) above sea level, it is one of the highest vehicular tunnels in the world. The tunnel is the longest mountain tunnel and highest point on the Interstate Highway System. Opened in 1973, the westbound bore is named after Dwight D. Eisenhower, the U.S. President for whom the Interstate system is also named. The eastbound bore was completed in 1979 and is named for Edwin C. Johnson, a Colorado governor and U.S. Senator who lobbied for an Interstate Highway to be built across Colorado.
Description
The Eisenhower Memorial Bore (westbound tunnel) is 1.693 miles (2.72 km) long, while the Edwin C. Johnson Memorial Bore (eastbound tunnel) is 1.697 miles (2.73 km) long. The tunnels are sloped with a 1.64% grade, with an elevation of 11,013 feet (3,357 m) at the east portal and 11,158 feet (3,401 m) at the west portal.
At its dedication, the Eisenhower Tunnel was the highest vehicular tunnel in the world. While it remains the highest vehicular tunnel in the US, and longest mountain tunnel and highest point on the Interstate Highway System, higher tunnels have since been constructed elsewhere, such as the Fenghuoshan Tunnel, a rail tunnel in China.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 1, 2026. The linked authority identifier is Q1312959. Authority coordinates are 39.679, -105.920. 2 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1973 and 1979.
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