The Diablo Range is a mountain range

Mountain range

A mountain range is a single, large mass consisting of a succession of mountains or narrowly spaced mountain ridges, with or without peaks, closely related in position, direction, formation, and age; a component part of a mountain system or of a mountain chain...

 in the California Coast Ranges subdivision of the Pacific Coast Ranges

Pacific Coast Ranges

The Pacific Coast Ranges and the Pacific Mountain System are the series of mountain ranges that stretch along the West Coast of North America from Alaska south to Northern and Central Mexico...

. It is located in the eastern San Francisco Bay area

San Francisco Bay Area

The San Francisco Bay Area, commonly known as the Bay Area, is a populated region that surrounds the San Francisco and San Pablo estuaries in Northern California. The region encompasses metropolitan areas of San Francisco, Oakland, and San Jose, along with smaller urban and rural areas...

 south to the Salinas Valley

Salinas Valley

The Salinas Valley lies south of San Francisco, California.The word "salina" is spanish for salt marsh, salt lake or salt pan.-Geography:The Salinas Valley runs approximately south-east from Salinas towards King City. The valley lends its name to the geologic province in which it's located, the...

 area of northern California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

, the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

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The Diablo Range extends from the Carquinez Strait

Carquinez Strait

The Carquinez Strait is a narrow tidal strait in northern California. It is part of the tidal estuary of the Sacramento and the San Joaquin rivers as they drain into the San Francisco Bay...

 in the north to Orchard Peak in the south, near the point where State Route 46

California State Route 46

State Route 46 is an east–west state highway in the U.S. state of California. It is a major crossing of the Coast Ranges, connecting SR 1 on the Central Coast near Cambria and US 101 in Paso Robles with SR 99 at Famoso in the San Joaquin Valley. East of Paso Robles, where it carried U.S...

 crosses over the Coast Ranges at Cholame, as described by the USGS. It is bordered on the northeast by the San Joaquin River

San Joaquin River

The San Joaquin River is the largest river of Central California in the United States. At over long, the river starts in the high Sierra Nevada, and flows through a rich agricultural region known as the San Joaquin Valley before reaching Suisun Bay, San Francisco Bay, and the Pacific Ocean...

, on the southeast by the San Joaquin Valley

San Joaquin Valley

The San Joaquin Valley is the area of the Central Valley of California that lies south of the Sacramento – San Joaquin River Delta in Stockton...

, on the southwest by the Salinas River

Salinas River (California)

The Salinas River is the largest river of the central coast of California, running and draining 4,160 square miles. It flows north-northwest and drains the Salinas Valley that slices through the Coast Range south from Monterey Bay...

, and on the northwest by the Santa Clara Valley

Santa Clara Valley

The Santa Clara Valley is a valley just south of the San Francisco Bay in Northern California in the United States. Much of Santa Clara County and its county seat, San José, are in the Santa Clara Valley. The valley was originally known as the Valley of Heart’s Delight for its high concentration...

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