Historic U.S. Route 66 crossed eight states from Illinois to California.
The highway passed through Illinois, Missouri, Kansas, Oklahoma, Texas, New Mexico, Arizona, and California. Although its route changed several times, these eight states remained associated with the historic corridor.
Route 66 was created in 1926 as part of the original U.S. Highway System. Its path connected Chicago with the Los Angeles area and later Santa Monica, crossing the central United States through major cities, small towns, farming regions, deserts, and mountain landscapes.
A common mistake is counting states that had related roads or later business routes rather than the official historic alignment. Kansas had the shortest section, but it was still one of the eight Route 66 states.