Eisenhower Tunnel

The Eisenhower Tunnel, officially the Eisenhower–Edwin C. Johnson Memorial Tunnel, is a dual-bore, four-lane vehicular tunnel approximately 50 mi (80 km) west of Denver, Colorado, United States. The tunnel carries Interstate 70 under the Continental Divide in the Rocky Mountains. With a maximum elevation of 11,158 ft (3,401 m) AMSL, 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. Completed in 1979, it was one of the last major pieces of the Interstate Highway system to be completed. The westbound bore is named after Dwight D. Eisenhower, the U.S. President for whom the Interstate system is also named. The eastbound bore is named for Edwin C. Johnson, a governor and U.S. Senator who lobbied for an Interstate Highway to be built across Colorado.

Description

The Eisenhower bore (westbound tunnel) is 1.693 mi (2.72 km) long while the Johnson bore (eastbound tunnel) is 1.697 mi (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 ft (3,401 m) at the west portal. At the time of dedication, they were the highest vehicular tunnels in the world. While the Eisenhower Tunnel remains the highest vehicular tunnel in the United States, higher tunnels have since been constructed elsewhere, such as the Fenghuoshan Tunnel, a rail tunnel in China. The Eisenhower tunnel is noted as the longest mountain tunnel and highest point on the Interstate Highway System. The tunnel bores measure 48 feet (15 m) by 40 feet (12 m); however, the portion accessible to the public is a square shape measuring just over 16 feet (4.9 m) tall. The rest of the bore is used for forced air ventilation and water drainage systems.

Interstate 70

Interstate 70 (I-70) is a major Interstate Highway in the United States that runs from a park and ride near Baltimore, Maryland, to I-15 near Cove Fort, Utah. I-70 approximately traces the path of U.S. Route 40 (US 40, the old National Road) east of the Rocky Mountains. West of the Rockies, the route of I-70 was derived from multiple sources. The Interstate runs through many major cities including Denver, Kansas City, St. Louis, Indianapolis, and Columbus.

The sections of the interstate in Missouri and Kansas have laid claim to be the first interstate in the United States. The Federal Highway Administration has claimed the section of I-70 through Glenwood Canyon, completed in 1992, was the last piece of the Interstate Highway system, as originally planned, to open to traffic.

The construction of I-70 in Colorado and Utah is considered an engineering marvel as the route passes through the Eisenhower Tunnel, Glenwood Canyon, and the San Rafael Swell. The Eisenhower Tunnel is the highest point along the Interstate Highway system with an elevation of 11,158 ft (3,401 m).

Surname

A surname or family name is a name added to a given name. In many cases, a surname is a family name and many dictionaries define "surname" as a synonym of "family name". In the western hemisphere, it is commonly synonymous with last name because it is usually placed at the end of a person's given name.

In most Spanish-speaking and Portuguese-speaking countries, two or more last names (or surnames) may be used. In China, Hungary, Japan, Korea, Madagascar, Taiwan, Vietnam, and parts of India, the family name is placed before a person's given name.

The style of having both a family name (surname) and a given name (forename) is far from universal. In many countries, it is common for ordinary people to have only one name or mononym.

The concept of a "surname" is a relatively recent historical development, evolving from a medieval naming practice called a "byname". Based on an individual's occupation or area of residence, a byname would be used in situations where more than one person had the same name.

Tunnel

A tunnel is an underground or underwater passageway, dug through the surrounding soil/earth/rock and enclosed except for entrance and exit, commonly at each end. A pipeline is not a tunnel, though some recent tunnels have used immersed tube construction techniques rather than traditional tunnel boring methods.

A tunnel may be for foot or vehicular road traffic, for rail traffic, or for a canal. The central portions of a rapid transit network are usually in tunnel. Some tunnels are aqueducts to supply water for consumption or for hydroelectric stations or are sewers. Utility tunnels are used for routing steam, chilled water, electrical power or telecommunication cables, as well as connecting buildings for convenient passage of people and equipment.

Secret tunnels are built for military purposes, or by civilians for smuggling of weapons, contraband, or people. Special tunnels, such as wildlife crossings, are built to allow wildlife to cross human-made barriers safely.

Terminology

A tunnel is relatively long and narrow; the length is often much greater than twice the diameter, although similar shorter excavations can be constructed, such as cross passages between tunnels.