Interstate 280 (I-280) is a 57.22-mile-long (92.09 km) major north–south auxiliary Interstate Highway in the San Francisco Bay Area of Northern California. It runs from I-680 and US Route 101 (US 101) in San Jose to King and 5th streets in San Francisco, running just to the west of the larger cities of San Francisco Peninsula for most of its route. I-280 is one of two auxiliary Interstate designations to appear on opposite coasts of the United States. I-110 in California and Florida is the only other designation.