Mount San Antonio

mountain, California, United States

Also known as: Mount Baldy, Old Baldy

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Last updated

July 16, 2026

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Mount San Antonio, also known as "Old Baldy," is the highest peak in the San Gabriel Mountains of southern California, reaching 10,064 feet (3,068 meters). The San Gabriel Mountains form a rugged range extending about 60 miles (100 km) from Newhall Pass and define the northern edge of the Los Angeles metropolitan area. Naturalist John Muir described these mountains as "rigidly inaccessible". Many peaks in this range exceed 9,000 feet. The San Gabriel Mountains are part of the Coast Ranges and are largely located within the Angeles National Forest. The southern foothills are known for citrus-fruit production.1

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Los Angeles
…Santa Catalina and San Clemente; Mount San Antonio, familiarly known as Mount Baldy or Old Baldy, 10,046 feet (3,062 metres) high; more than 900 square miles (2,330 square km) of desert; and 75 miles (120 km) of seacoast.
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…Santa Catalina and San Clemente; Mount San Antonio, familiarly known as Mount Baldy or Old Baldy, 10,046 feet (3,062 metres) high; more than 900 square miles (2,330 square km) of desert; and 75 miles (120 km) of seacoast.
Read More