U.S. Route 66 or U.S. Highway 66 (US 66 or Route 66) was one of the original highways in the United States Numbered Highway System. Established on November 11, 1926, with signage erected the following year, the highway ran from Chicago, Illinois, through Missouri, Kansas, Oklahoma, Texas, New Mexico, and Arizona before terminating in Santa Monica, California, covering 2,448 miles (3,940 km).
US 66 became a major route for westward migration, particularly during the Dust Bowl of the 1930s, and contributed to the economic development of communities along its path. It later faced decline as traffic was diverted to the Interstate Highway System in the mid-20th century.
The highway was officially removed from the United States Highway System in 1985 after being largely replaced by Interstate highways. Many segments of the former route have since been preserved as Historic Route 66, a National Scenic Byway, and incorporated into state and local road systems.
Route 66 has been widely represented in American popular culture and is often referred to by nicknames such as the Mother Road, a term popularized by John Steinbeck's novel The Grapes of Wrath (1939), as well as the Main Street of America and the Will Rogers Highway. The road and impact of the Interstate Highway System bypassing small towns along the route was central to the story in Disney's 2006 animated film Cars.
-Wikipedia