Along the center line of the Peninsula is the northern half of the
Santa Cruz Mountains, formed by the action of
plate tectonics along the
San Andreas Fault. In the middle of the Peninsula along the fault is the
Crystal Springs Reservoir. Just north of the Crystal Springs reservoir is
San Andreas Lake, after which the
geologic fault was originally named. The east side of the peninsula is a densely populated and largely urban and suburban area that includes portions of Silicon Valley. It forms a commuter area between San Francisco to the north and
San Jose to the south.
Roads •
Interstate 80 •
Interstate 280 •
Interstate 380 •
U.S. Route 101 •
State Route 1 •
State Route 9 •
State Route 35 •
State Route 82 •
State Route 84 •
State Route 85 •
State Route 92 •
State Route 109 •
State Route 114 •
State Route 237 The bridges in the Peninsula include the
Dumbarton Bridge, the
Golden Gate Bridge, the
San Francisco - Oakland Bay Bridge, and the
San Mateo–Hayward Bridge. A number of major thoroughfares run north-south:
El Camino Real (
SR 82) and
US 101 on the east side along the bay,
Interstate 280 down the center,
Skyline Boulevard (
SR 35) along the crest of the
Santa Cruz Mountains, and
SR 1 on the west along the Pacific, and
SR 85 which forms the southern end of the Peninsula.
Transit Caltrain is the primary passenger rail transit in the peninsula, serving much of the eastern urbanized areas of the peninsula between Mountain View (which also connects to
VTA light rail) and San Francisco's
4th and King Street station. In addition, the peninsula has access to
Bay Area Rapid Transit (BART) northward of
Millbrae, connecting San Mateo County and San Francisco to the
East Bay through a route over and under
Daly City,
Glen Park,
San Francisco's Mission district, and through part of
Market Street subway. Bus service is predominantly provided by
SamTrans and the
SFMTA's Muni buses, which primarily run in San Mateo and San Francisco counties respectively. In addition, southward of Palo Alto, the
Santa Clara Valley Transportation Authority operates buses to other parts of Santa Clara County. Most of the peninsula's bus transit to the
East Bay and
North Bay flowing through San Francisco, as neither
AC Transit nor
Golden Gate Transit, the primary transit operators for the East and North Bay respectively, serve the peninsula south of San Francisco.
Airports The peninsula's largest commercial airport is
San Francisco International Airport, itself connected to US 101 and BART and accessible to Caltrain (via a BART connection at Milbrae station).
San Jose International Airport, is the next largest airport in the region serving and might be a more viable option for the southern peninsula. The airport is connected to US 101 and there is a single connector bus,
VTA Line 60, that links to Caltrain (at Santa Clara Transit Center) and to eastern lines of BART (Milpitas).
Oakland San Francisco International Airport, located in the
East Bay, is the smallest of the three and is also accessible directly via BART. ==Environmental features==