State Route 16 (SR 16) is a state highway in the northern region of the U.S. state of California that runs from Route 20 in Colusa County to Route 49 just outside Plymouth in Amador County, primarily crossing the Sacramento Valley. Much of the route through the Sacramento area is unsigned as it runs on a concurrency with the I-5 and US 50 freeways. Route description SR 16 is part of the California Freeway and Expressway System, and the eastern segment is part of the National Highway System, a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration. SR 16 is eligible to be included in the State Scenic Highway System, but it is not officially designated as a scenic highway by the California Department of Transportation. It is known as the Stanley L. Van Vleck Memorial Highway from Dillard Road in Sacramento County to the Amador County line, honoring a former prominent leader in the state's agricultural organizations. State Route 16 begins in Colusa County near Wilbur Springs at the junction with State Route 20. SR 16 goes south alongside Bear Creek, which enters a narrow canyon and joins with Cache Creek near the Yolo County line. SR 16 continues in the canyon, running close to the river, passing Cache Creek Canyon Regional Park, and emerging from the canyon north of Rumsey. This section is so prone to rock slides that there are permanent gates at each end. SR 16 continues to parallel Cache Creek, at a greater distance, going south-east through Capay Valley, with Blue Ridge to its west and the Capay Hills (including Bald Mountain) to its east. It goes through Rumsey, Guinda, Brooks, Cache Creek Casino Resort, Capay, Esparto (intersecting with County Route E4 to Dunnigan), and Madison. East of Madison, and now in the Central Valley, SR 16 interchanges with Interstate 505 before heading east toward Woodland. In west Woodland it merges with County Road 22 and then turns north, concurrently with County Route E7 and Interstate 5 Business, until it meets its interchange with Interstate 5. SR 16 then runs on I-5 from Woodland towards Sacramento in an unsigned concurrency. At the junction with US 50 in the southeastern part of Downtown Sacramento, SR 16 turns eastward on an unsigned concurrency with US 50. It then diverges from US 50 via Howe Ave., goes