The Santa Clara Valley (Spanish: Valle de Santa Clara) is a geologic trough in Northern California that extends 90 miles (140 km) south–southeast from San Francisco to Hollister. The longitudinal valley is bordered on the west by the Santa Cruz Mountains and on the east by the Diablo Range; the two coastal ranges meet south of Hollister. The San Francisco Bay borders the valley to the north, and fills much of the northern third of the valley. The valley floor is an alluvial plain that formed in the graben (tectonic depression) between the San Andreas Fault to the west and the Hayward and Calaveras faults to the east. Within the valley and surrounding the bay on three sides are the urban communities of San Mateo County, Santa Clara County, and Alameda County, while the narrow southern reaches of the valley extend into rural San Benito County to Hollister. In practical terms, the central portion of the Santa Clara Valley is often considered by itself, contained entirely within Santa Clara County.
The valley, named after the Spanish Mission Santa Clara, was for a time known as the Valley of Heart’s Delight for its high concentration of orchards, flowering trees, and plants. Until the 1960s it was the largest fruit-producing and packing region in the world, with 39 canneries. The growing high-tech industry in the 1960s transformed the area from farmland to densely populated cities, and it became referred to as Silicon Valley.
Once primarily agricultural because of its highly fertile soil, Santa Clara Valley is now largely urbanized, although its far southern reaches south of Gilroy remain agrarian. Few traces of its agricultural past can still be found, but the Santa Clara Valley American Viticultural Area remains a large wine-making region. It was one of the first commercial wine-producing regions in California (and possibly the United States), utilizing high-quality French varietal vines imported from France.
The northern end of the Santa Clara Valley is at San Francisco, and the southern end is south of Hollister. The valley is bounded by the Santa Cruz Mountains on the southwest, which separate the valley from the Pacific Ocean, and by the Diablo Range on the northeast. The valley is approximately 93 miles (150 km) long by 15 miles (20 km) wide. Its largest city is San Jose. Santa Clara Valley has a Mediterranean semi-arid climate.
Because technology companies have spread out from Silicon Valley, Fremont and Newark, even though they are not in Santa Clara County, are often included in discussions about Silicon Valley, or, in the case of Fremont, referred to as the “Gateway to the Silicon Valley” (a title also claimed occasionally by San Jose, Union City, and several other locations). Similarly, Palo Alto, while in Santa Clara County and considered part of Silicon Valley, is on the San Francisco Peninsula. There are a number of well-known structures and sites of interest in the South Bay (tourist attractions in Santa Clara Valley):
