Southlandtraffic.net
- Covers various details in the southern part of the state. Includes a weblog.
- http://www.southlandtraffic.net/

DLK's Highway Page
- Several freeway plans for the San Francisco Bay Area and California highway signs.
- http://www.kriske.com/highway/

The Ups & Downs of Highway 1 (Smithsonian Magazine)
- Addresses the erosion problem on the Pacific Coast Highway (SR 1).
- http://www.smithsonianmag.com/issues/1999/june/highway.php

Transportation Corridor Agencies
- Builds and manages toll roads in Orange County. Includes toll and transponder information, proposed extensions, and discounts.
- http://www.thetollroads.com/

I-680 Smart Lane
- A section of the southbound carpool lane in Alameda and Santa Clara Counties is being considered for conversion to a Smart Carpool Lane or High Occupancy Toll (HOT) Lane.
- http://680smartlane.org/

South Bay Expressway
- Automated FasTrak toll road in San Diego to open Fall 2006 that will service Chula Vista, Bonita, and Otay Mesa, connecting SR-54 to the Mexico border as part of SR-125. Site includes news and project overview.
- http://www.southbayexpressway.com/

HaltTheRamp.com
- Citizen's campaign against the plan to reconstruct the end of San Francisco's Central Freeway. Site includes historical background and links to official sites.
- http://www.halttheramp.com/

Widen I-205 Now
- Group wishing to petition the state government to allot money for the widening of the highway near Tracy. Site includes event listing and news.
- http://www.205now.com/

Floodgap Roadgap
- Documents unusual and former routings in the southern part of the state. Includes photographs.
- http://www.floodgap.com/roadgap/

California FasTrak
- This electronic toll collection system lets drivers electronically pay tolls on California's bridges and toll roads without stopping.
- http://www.511.org/fastrak/

Freeways of San Francisco
- Photos and information on some built and unbuilt freeways.
- http://www.pcpages.com/sanfrancisco/

ReBuild California
- Labor/contractor group advocating increased public investment in state infrastructure, including mass transit and highways.
- http://www.rebuildca.org/

Friends of Southern California's Highways
- A community grass-roots organization dedicated to the rebuilding and expansion of the regional freeway and thoroughfare system.
- http://www.fixtraffic.org/

California Highways @ WestCoastRoads.com
- Statewide coverage.
- http://www.westcoastroads.com/california/

In Our Path
- Describes the process of the construction of I-105 (Century Freeway) near Los Angeles.
- http://www.outtacontext.com/iop/

Dr. Roadmap, LLC
- Information on both a book and a board game on Los Angeles alternate routes, as well as information on their creator.
- http://www.drroadmap.com/

California Motorcycle Roads
- Descriptions of scenic and challenging backroads.
- http://www.pashnit.com/motoroads.htm

Casey's Roads and Highways Page
- Covers many aspects, including Historic U.S. highways and the unusually-numbered I-238.
- http://gbcnet.com/roads/

The Ridge Route Preservation Organization
- Maps, photos and history of the pioneer highway between Bakersfield and Los Angeles.
- http://www.ridgeroute.com

California Highway Patrol Traffic Incident Information
- Live traffic incident information from the CHP computer system.
- http://cad.chp.ca.gov

Unofficial Road Information For Highway 1, Big Sur
- Information about old closures of SR 1 (Pacific Coast Highway) at Big Sur due to a landslide.
- http://www.surcoast.com/road.html

California Highways and Bridges
- Photos, articles and vintage construction information about California's road network.
- http://members.cox.net/mkpl/road.html

Historic Highways of Southern and Central California
- Examines the area's highway past, present and future.
- http://www.scvresources.com/highways/

Jeff's Streets Page
- Information, ideas, and views on Northern California facilities, with an emphasis on the Santa Cruz and Monterey Bay areas.
- http://we.got.net/~mapman/streets/

Advanced Highway Maintenance and Construction Technology Research Center
- UC Davis and Caltrans highway research center.
- http://www.ahmct.ucdavis.edu/

91 Express Lanes
- Information on the toll roadways on the Riverside Freeway (State Route 91) in metro Los Angeles.
- http://www.91expresslanes.com/

SigAlert.com
- Includes live freeway speed maps and traffic incident summaries for many locations around the state.
- http://www.sigalert.com/