- Another Interstate 580 exists in Reno, Nevada, but is signed only as US 395.
- The Interstate 580 number was also used for part of US 75 in Omaha, Nebraska.
Interstate 580 (MacArthur Freeway) in northern California is a heavily traveled, fairly long spur route of Interstate 80 that connects the San Francisco Bay Area to Interstate 5 in the state's Central Valley. The western terminus of I-580 is north of San Francisco in San Rafael, at a junction with U.S. Highway 101. The eastern terminus is with I-5 southeast of Tracy. It was named after General Douglas MacArthur in 1968. Leaving San Rafael, I-580 runs next to the San Quentin State Prison before crossing San Francisco Bay over the Richmond-San Rafael Bridge.
Major cities
Intersections with other Interstates
Notes
On the section of 10-lane freeway that is designated both I-80 and I-580, from Emeryville to Albany, the two routes are running in opposite directions. That is, while a vehicle is physically moving north on the road, it is on both I-80 East and I-580 West.