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 through Tejon Pass and down through the San Emigdio Mountains to the San Joaquin Valley, where it followed a route along the eastern slopes of the Coast Ranges between aguaje (watering places) and arroyos. 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.[1][2][3]