List of tunnels in California

The following is a list of tunnels in California.

Mass transit

 * Altamont Corridor Express
 * (two) Union Pacific Railroad (formerly Western Pacific Railroad) in Niles Canyon, Alameda County: one 4,500 ft long and the other 450 ft long
 * BART
 * Balboa Park station complex
 * Berkeley Hills Tunnel, rapid transit tunnel, BART beneath Grizzly Peak between Orinda and Oakland
 * Berkeley Subway, beneath Berkeley
 * Broadway Subway in Oakland, including the Oakland Wye
 * Fremont Central Park Subway, underneath Lake Elizabeth
 * Market Street subway twin level rapid transit and light rail tunnel beneath Market Street in San Francisco (shared with Muni Metro)
 * Milpitas station
 * Lundy/Sierra tunnel
 * Silicon Valley BART extension Phase 3 (planned)
 * Transbay Tube, rapid transit tunnel, BART beneath San Francisco Bay between Oakland and San Francisco
 * San Francisco International Airport extension
 * Caltrain
 * (five) Bayshore Cutoff, originally built by the Southern Pacific railroad, tunnel 5 abandoned in 1956
 * The Portal (proposed)
 * Transbay Transit Center train box
 * Los Angeles Metro Rail
 * (three) K Line (under construction)
 * Figueroa Tunnel, on the E Line
 * Flower Street tunnel, carrying the A and E Lines to the 7th Street/Metro Center station
 * L Line subway, between Indiana and Pico/Aliso stations
 * Los Angeles Subway, including the B Line and D Line
 * Regional Connector (under construction)
 * Metrolink
 * San Fernando Tunnel, rail tunnel, Union Pacific Railroad (formerly Southern Pacific Railroad), Santa Clarita
 * (three) Simi Valley Tunnels/Santa Susana Tunnels, rail tunnels, Union Pacific Railroad (formerly Southern Pacific Railroad), between Los Angeles and Simi Valley through the Santa Susana Mountains; the longest and westernmost is Tunnel No. 26
 * San Francisco Municipal Railway (Muni Metro)
 * Central Subway
 * Sunset Tunnel, light rail tunnel beneath Buena Vista Park
 * Twin Peaks Tunnel, light rail tunnel beneath Twin Peaks
 * Market Street subway twin level rapid transit and light rail tunnel beneath Market Street in San Francisco (shared with BART)
 * Sonoma–Marin Area Rail Transit
 * Cal Park Hill Tunnel, beneath California Park, also features a pedestrian/bicycle path
 * Puerto Suello Hill Tunnel, commuter rail tunnel
 * San Diego State University Transit Center, the only subway station in the San Diego Trolley system
 * VTA light rail tunnel under San Jose Diridon station

Abandoned

 * Belmont Tunnel/Toluca Substation and Yard
 * (five) North Pacific Coast Railroad tunnels, including:
 * Alto Tunnel
 * Tunnel 8, former Northwestern Pacific Railroad tunnel
 * Shepherd Canyon, used by the Sacramento Northern Railway
 * (five) Summit, Laurel, Zayante, Tunnel 5, and Mountain Charlie Tunnels; built by the South Pacific Coast Railroad (Tunnel 7 daylighted c. 1950s)

Freight and intercity rail

 * Fort Mason Tunnel, former rail tunnel beneath Fort Mason, San Francisco
 * Point Richmond Tunnel, carrying BNSF freight parallel to the road tunnel in Point Richmond
 * Summit Tunnel (Tunnel No. 6), abandoned rail tunnel, Central Pacific Railroad, one of a number through the Donner Pass area of the Sierra Nevada
 * The Big Hole, Tunnel No. 41, built to replace Tunnel No. 6 through the Donner Pass and carrying the Union Pacific Railroad
 * (34) Feather River Route, including:
 * Chilcoot Tunnel
 * Spring Garden Tunnel
 * Keddie Wye, tunnels Tunnel No. 31 and No. 32 in the wye complex
 * Mission Tunnel, below Mission Santa Cruz and used by the Santa Cruz, Big Trees and Pacific Railway
 * (three) BNSF Gateway Subdivision
 * (three) BNSF Stockton Subdivision, including:
 * Franklin Tunnel
 * (six) Union Pacific Coast Subdivision
 * Tunnel No. 6 (Coast Line)
 * Tehachapi Loop Tunnel, rail tunnel, 1876, Union Pacific Railroad (formerly, Southern Pacific Railroad), just north of State Route 58 between Tehachapi and Bakersfield

Excursion

 * (two) California Western Railroad, popularly called the Skunk Train

Automotive

 * Collier Tunnel, Redwood Highway (US 199), Del Norte County
 * Dornan Tunnel, carrying Gerrard Avenue in Point Richmond parallel to the rail tunnel
 * Escondido Freeway (SR 15), cut-and-cover tunnel between Polk and Orange Avenues in East San Diego (Teralta Park covers the freeway)
 * Feather River Highway (SR-70), three tunnels, Feather River Canyon
 * Gaviota Tunnel, northbound US 101, Santa Barbara County
 * Harry Crabb Tunnel, ramp to eastbound Interstate 80 (Alan S. Hart Freeway) from northbound Sunrise Avenue (south of Douglas Boulevard) in Roseville
 * John F. Foran Freeway (I-280), (southbound only) at its interchange with the 19th Avenue (SR 1) in Daly City
 * Lighthouse Avenue Tunnel, Monterey
 * Tom Lantos Tunnels/Devil's Slide Tunnels, twin tunnels, SR 1 beneath Devil's Slide between Pacifica and Montara
 * Tunnels to Nowhere, two tunnels, Shoemaker Canyon Road (unpaved), San Gabriel Mountains
 * Big Oak Flat Road, three tunnels, Yosemite National Park
 * Wawona Tunnel, Wawona Road (SR 41), Yosemite National Park, the longest road tunnel in California at 4,233 ft

Alameda County

 * 11th Street Tunnel, under the Oakland Museum of California in Oakland
 * Caldecott Tunnel, quad tunnels, SR 24 beneath Grizzly Peak between Orinda and Oakland
 * Northbrae Tunnel, former East Bay Electric Lines rail tunnel, current road tunnel joining Solano Avenue and Sutter Street beneath Marin Circle, Berkeley
 * Posey and Webster Street Tubes, twin immersed tubes, SR 61 beneath the Oakland Estuary between Alameda and Oakland

Los Angeles County

 * Airport Tunnel, twin tunnels, Sepulveda Boulevard (SR 1) beneath Runways 7L/25R and 7R/25L at Los Angeles International Airport, Los Angeles
 * Angeles Crest Highway (State Route 2), two sets of tunnels in the San Gabriel Mountains National Monument northeast Los Angeles County between La Cañada Flintridge and Wrightwood
 * Angeles Forest Highway Tunnel/Singing Springs Tunnel/Hidden Springs Tunnel, Angeles Forest Highway/County Road N3, San Gabriel Mountains National Monument, north Los Angeles County between La Cañada Flintridge and Palmdale
 * Broadway Tunnel extended Broadway further north, later demolished
 * Kanan Dume Tunnel, north of Malibu
 * Malibu Canyon Tunnel
 * Figueroa Street Tunnels, northbound Arroyo Seco Parkway (SR 110), four tunnels beneath Elysian Park, Los Angeles
 * Foothill Freeway (I-210)
 * Cut-and-cover tunnel between Glendale Freeway and Angeles Crest Highway (both part of State Highway 2) in La Cañada Flintridge (Memorial Park covers the freeway)
 * Two short tunnels (eastbound only) under SR 710 and Ventura Freeway (SR 134) in Pasadena
 * Griffith Park Tunnel, Vermont Canyon Road/Mount Hollywood Drive in Griffith Park, Los Angeles
 * Long Beach Airport tunnels, two sets of twin tunnels for Lakewood Boulevard (SR 19) and Spring Street under runway 12/30 at Long Beach Airport, Long Beach
 * McClure Tunnel, SR 1 located at the western terminus of I-10 in Santa Monica
 * Mount Baldy Road, two tunnels, north of Claremont
 * Newhall Pass Tunnels, two tunnels about 550 ft each, southbound truck bypass lanes of the Golden State Freeway (I5), in Santa Clarita and Los Angeles
 * Orange Freeway (SR 57), (northbound only) at its interchange with the Pomona Freeway (SR 60) in Diamond Bar
 * Santa Ana Freeway portion of US 101 (northbound only), at its interchange with the San Bernardino Freeway (SR 10) in downtown Los Angeles
 * Second Street Tunnel, beneath Bunker Hill, downtown Los Angeles
 * Third Street Tunnel, beneath Bunker Hill, downtown Los Angeles
 * Sepulveda Boulevard Tunnel, Sepulveda Boulevard under Mulholland Drive at the north end of Sepulveda Pass, Los Angeles
 * Van Nuys Airport Tunnel, twin tunnels, Sherman Way under runway 16R/34L at Van Nuys Airport, west San Fernando Valley, Los Angeles

Marin County

 * Baker-Barry Tunnel, single lane tunnel, Bunker Rd, Sausalito
 * Robin Williams Tunnel/Waldo Tunnel, twin tunnels, US 101 and SR 1, Sausalito

Orange County

 * Main Street under the Santa Ana Freeway (I5) in Tustin, California
 * SR 133 segment of the Eastern Transportation Corridor toll road, (northbound only) at its interchange with the SR 241 (Foothill Transportation Corridor) in Irvine
 * SR 261 segment of the Eastern Transportation Corridor toll road, (northbound only) at its interchange with the SR 241 (Eastern Transportation Corridor) in Orange

San Francisco

 * Broadway Tunnel, twin tunnels, Broadway beneath Russian Hill
 * MacArthur Tunnel, SR 1 beneath the Presidio of San Francisco (Golden Gate National Recreation Area)
 * Masonic Tunnel, carrying Geary Boulevard under Masonic Avenue
 * Presidio Parkway, US 101 through the Presidio of San Francisco (replacement for the elevated Doyle Drive)
 * Stockton Street Tunnel, beneath a portion of Chinatown
 * Yerba Buena Tunnel, twin tunnels, I-80 near the middle of the San Francisco–Oakland Bay Bridge complex, Yerba Buena Island

Abandoned

 * Kennedy Tunnel, former road above the extant Caldecott Tunnel (see above)

Utility

 * Angeles Tunnel
 * Claremont Tunnel
 * Hetch Hetchy Coast Range tunnel
 * (three) Inland Feeder
 * Arrowhead West Tunnel
 * Arrowhead East Tunnel
 * Riverside Badlands Tunnel
 * Mile Rock
 * San Jacinto Tunnel
 * South Bay Aqueduct
 * Trinity Diversion Tunnel: a 10.7 mile tunnel diverting water from the Trinity Basin to the Sacramento Valley.

Mining

 * Burro Schmidt Tunnel, mining tunnel, east of Red Rock Canyon State Park, eastern Kern County

Military and Industry

 * SpaceX constructed a 1.4 Mile test tunnel underneath the parking lot of its Hawthorne plant for experimental transportation technology.
 * United States Airforce Plant 42 in Palmdale is rumored to have an underground network of tunnels connecting to nearby defense plants including Lockheed's Skunk works.
 * Ft. McArthur Tunnel Complex: an abandoned World War II network connecting fortifications in San Pedro, CA.
 * The Lawson Adit is a tunnel constructed underneath UC Berkeley into the Berkeley Hills in the early 1900s for student mining research.
 * US Dept. of Defense Tunnel Warfare Center, China Lake
 * The Stanford Linear Accelerator operates in a 10,000-foot concrete tunnel, 25 feet underground.
 * Vandenberg Space Force Base has a number of underground tunnels to support rocket launch operations.