Interstate 5 in California

Interstate 5 (I-5) is a major north–south route of the Interstate Highway System in the United States, running largely parallel to the Pacific Coast between the Mexican border and the Canadian border. The segment of I-5 in California runs across the length of the state from the Mexican border at the San Ysidro Port of Entry in the San Ysidro neighborhood of San Diego to the Oregon state line south of the Medford-Ashland metropolitan area. It is the longest interstate in California at 796.77 miles (1,282.28 km), and accounts for more than half of I-5's total length of 1,381.29 miles (2,222.97 km). It is also the second longest stretch of Interstate Highway with a single designation within a single state after I-10 in Texas.