U.S. Route 101 (US 101) is a major north–south United States Numbered Highway, stretching from Los Angeles, California, to Tumwater, Washington. The California portion of US 101 is one of the last remaining and longest U.S. Routes still active in the state, and the longest highway of any kind in California. US 101 was also one of the original national routes established in 1926. Significant portions of US 101 between the Los Angeles area and the San Francisco Bay Area follow El Camino Real, the commemorative route connecting the former Alta California's 21 missions.
Although the highway has been superseded in overall importance for transportation through the state by Interstate 5 (I-5), US 101 continues to be the major coastal north–south route that links the Greater Los Angeles Area, the Central Coast, the San Francisco Bay Area, and the North Coast (Redwood Empire). Generally referred to as "101" by residents of Northern California, in Southern California it is often called "The 101" (pronounced "the one oh one"). The highway has portions designated as the Santa Ana Freeway, the Hollywood Freeway, the Ventura Freeway, South Valley Freeway, and Bayshore Freeway, as well as El Camino Real in many non-freeway segments. The Redwood Highway, the 350-mile-long (560 km) northernmost segment of the highway, begins at the Golden Gate and passes through the world's tallest and only extensive preserves of virgin, old-growth coast redwood trees.
