&sq=Google&lang=en&file=File:I-380_(CA).svg) Interstate 380 | ||||
|---|---|---|---|---|
| Quentin L. Kopp Freeway | ||||
 I-380 highlighted in red | ||||
| Route information | ||||
| Maintained by Caltrans | ||||
| Length | 3.3 mi[1] (5.3 km) | |||
| Existed | 1964–present | |||
| NHS | Entire route | |||
| Major junctions | ||||
| West end |  I-280 in San Bruno | |||
| East end |  US 101 in South San Francisco | |||
| Location | ||||
| Country | United States | |||
| State | California | |||
| Counties | San Mateo | |||
| Highway system | ||||
| ||||
Interstate 380 (I-380) is a short 3.3-mile (5.3 km) east–west auxiliary Interstate Highway in the San Francisco Bay Area of Northern California, connecting I-280 in San Bruno to US Route 101 (US 101) near San Francisco International Airport. The highway primarily consists of only three intersections: I-280, State Route 82 (SR 82/El Camino Real), and US 101. Like the nearby I-280, I-380 never connects to I-80, its parent Interstate Highway. However, there is no rule that says that spur routes need to do so. (Similarly, the spur route I-795 branches off from I-695, a beltway around Baltimore, and is only indirectly linked to I-95.)
I-380 is officially known as the Quentin L. Kopp Freeway, named after the prominent California state senator from San Mateo County. This highway was previously named the Portola Freeway to honor the 18th-century Spanish explorer Gaspar de Portolá, whose expedition in 1769–1770 discovered the San Francisco Bay, from a viewpoint on the Sweeney Ridge located between San Bruno and Pacifica.
- ^ "Table 2: Auxiliary Routes of the Dwight D. Eisenhower National System Of Interstate and Defense Highways". FHWA Route Log and Finder List. Federal Highway Administration. December 31, 2021. Retrieved July 6, 2022.