is a north-south highway in the southeastern part of the
San Francisco Bay Area , USA. A divided multilane surface highway, it connects
Interstate 580 in
Castro Valley, California and
Interstate 680 in
Fremont, California . It goes through
Hayward and
Union City parallel to the
Hayward Hills . It formerly contained a segment of east-west freeway now designated as
Interstate 238 and, until Interstate 680 was completed in the area and supplanted it completely as a through route, extended to
San José, California at its intersection with
U.S. Route 101 .
Before California massively renumbered its state highways in 1964, this highway was known as
California State Route 9 . It was long scheduled for replacement by a freeway.
California Streets and Highways Code, Chapter 2, Article 3, Section 538
