Interstate 280 (California)

Interstate 280 (California) is a major north–south Interstate Highway in the San Francisco Bay Area of Northern California. It runs approximately 57 miles from its southern terminus at the interchange of Interstate 680 and U.S. 101 in San Jose to its northern terminus in the South of Market district of San Francisco. Known for its scenic route through the Santa Cruz Mountains and along the San Francisco Peninsula, it is officially named the Junípero Serra Freeway south of its junction with I-680 and the Sinclair Freeway to the north, providing a vital bypass of the more congested U.S. 101 corridor.

Route description

From its southern terminus at the complex interchange with I-680 and U.S. 101 in San Jose, I-280 heads northwest through the Silicon Valley cities of Cupertino and Los Altos. The highway then enters a notably scenic segment, traversing the Santa Cruz Mountains via the Searsville Lake area and passing near landmarks like Filoli estate. It continues north along the western flank of the San Francisco Peninsula, offering views of the Crystal Springs Reservoir and the San Andreas Fault zone, before entering San Francisco. Within San Francisco, it passes through the Twin Peaks tunnel and terminates at an intersection with King Street and 5th Street near the Giants' Oracle Park and the San Francisco Bay.

History

The route of I-280 was established as part of the federal Interstate Highway System in the 1950s, with construction beginning in the early 1960s. A significant engineering achievement was the completion of the Twin Peaks Tunnel section in San Francisco in 1967. The freeway's alignment was controversial, particularly through San Mateo County, where community opposition led by Crystal Springs area residents successfully prevented a planned extension that would have connected directly to the Golden Gate Bridge. The freeway was fully opened to traffic by 1974. It has since undergone major seismic retrofit projects, including work on the Southern Freeway viaduct in San Jose following the 1989 Loma Prieta earthquake.

Major intersections

The entire route is in the San Francisco Bay Area. Key junctions include the southern terminus at I-680/US 101 in San Jose. It intersects State Route 85 in Cupertino and State Route 92 near the San Mateo–Hayward Bridge. In San Francisco, it meets Interstate 380 and has a major interchange with U.S. 101 (the James Lick Freeway) before reaching its northern terminus. All junctions are at-grade separated interchanges.

Exit list

Exits are numbered sequentially from south to north. Notable exits include Exit 1 for Almaden Expressway in San Jose, Exit 8 for De Anza Boulevard serving De Anza College, and Exit 25 for Edgewood Road providing access to Pulgas Ridge Open Space Preserve. In San Mateo County, Exit 34 serves SR 92. Within San Francisco, key exits include Exit 47B for I-380, Exit 49 for U.S. 101, and the final exits for 6th Street and King Street near Oracle Park.

See also

* Interstate Highway System * California State Route 1 * Transportation in the San Francisco Bay Area * Santa Cruz Mountains * Junipero Serra

Category:Interstate Highways in California Category:Transportation in San Francisco Category:Transportation in San Jose, California Category:San Mateo County, California