El Camino Viejo

El Camino Viejo a Los Ángeles (English: the Old Road to Los Angeles), also known as El Camino Viejo and the Old Los Angeles Trail, was the oldest north-south trail in the interior of Spanish colonial Las Californias (1769–1822) and Mexican Alta California (1822–1848), present day California. It became a well established inland route, and an alternative to the coastal El Camino Real trail used since the 1770s in the period.

It ran from San Pedro Bay and the Pueblo de Los Ángeles, over the Transverse Ranges and down Old Tejon Pass, up the San Joaquin Valley along the eastern slopes of the Coast Ranges following a route between aguaje (watering places) and arroyos (creeks). It passed west out of the valley, over the Diablo Range at Corral Hollow Pass into the Livermore Valley, to end at the Oakland Estuary on the eastern San Francisco Bay.

The route of El Camino Viejo was well established by the 1820s, and the route was in use by Spanish colonial "carretas" (ox carts) as early as 1780, as a more direct route than El Camino Real to the recently established Mission Santa Clara de Asís and Mission San Francisco de Asís. At that time the Bay Area section ran from the mouth of Arroyo Las Positas southwest across the mouth of the Arroyo Mocho and Arroyo Valle to Arroyo de la Laguna (later the lands of Rancho Valle de San Jose) and following it south down to its confluence with Arroyo de la Alameda (later location of Sunol). It then crossed the hills to the south via Mission Pass to the coastal plain and on until it reached Mission Santa Clara and the El Camino Real. The Los Angeles Area section left the El Camino Real in the San Fernando Valley,

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