San Gabriel Valley
The San Gabriel Valley is one of the principal valleys of Southern California, lying generally to the east of the city of Los Angeles. Surrounding features include:
The valley derives its name from the San Gabriel River that flows southward through the center of the valley, which itself was named for the Spanish Mission San Gabriel Arcángel originally built in the Whittier Narrows in 1771.
At one time predominantly agricultural, the San Gabriel Valley is today almost entirely urbanized and is an integral part of the Greater Los Angeles metropolitan area. It is one of the most ethnically diverse regions in the country. About 200 square miles (520 km2) in size, the valley includes thirty-one cities and five unincorporated communities.
In 1886, Pasadena was the first independent incorporated city still located in Los Angeles County (both Anaheim and Santa Ana are now located in Orange County).
The San Gabriel Valley is in Los Angeles County. The incorporated cities and unincorporated neighborhoods of the San Gabriel Valley include:
Whittier, like Montebello, is considered both a San Gabriel Valley city and part of the Gateway Cities region. Some of Whittier sits below the Puente Hills. Although these hills are small compared to the San Gabriel Mountains, the fact that most of the city sits around them makes Whittier a San Gabriel Valley city. This is similar to Montebello, which is a member of the Gateway Cities Council of Governments, despite geographically being part of the San Gabriel Valley.
Claremont, Diamond Bar, La Verne, Pomona, San Dimas and Walnut are adjacent to the San Gabriel Valley, and although are properly considered part of the Pomona Valley, they are also commonly considered part of the San Gabriel Valley. The 57 Freeway (Orange Freeway) is generally considered the dividing line between the Pomona and San Gabriel valleys. However, for statistical and economic development purposes, the County of Los Angeles generally includes these six cities as part of the San Gabriel Valley. The community of El Sereno, in the city of Los Angeles, is situated at the westernmost edge of the Valley. Unofficial estimates place the combined population of the San Gabriel Valley at around 2 million—roughly a fifth of the population of Los Angeles County.
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