Slover Mountain in 1906.
Slover Mountain, also known as Mount Slover and Marble Mountain, is a former landmark in south Colton. It was also referred to as Tahualtapa (Raven Hill) by Native Americans and Cerrito Solo (Little Solitary Hill) by the Colonial Spanish.
Many of Southern California’s early explorers quickly discovered the mountain’s wealth of mineral deposits. Before Slover Mountain was mined for marble and limestone, it stood as the tallest mountain in the San Bernardino Valley at 1,184 feet.
The mountain was named after Isaac Slover, one of the early explorers. Slover and his wife moved to California in the 1830s and opted to settle east, near the community of Agua Mansa. Slover and his wife lived in a small adobe home at the base of the mountain where he became a pillar of early Inland Southern California.
The Slover couple had a reputation for their kindness and hospitality, offering supplies, food and lodging to weary travelers. By the 1860s, settlers in the Agua Mansa area south of Mount Slover built kilns near the base of the mountain to burn its abundant limestone to create mortar and plaster.
The Colton Marble Lime Company was founded in 1881 to make use of the marble quarries that Mt. Slover had to offer. It is said that some of the finest homes in Los Angeles and San Francisco were built using marble from Mount Slover.
The California Portland Cement Company of Colton began extracting limestone from the mountain to manufacture cement in 1894. It became the first cement plant west of the Rocky Mountains.
In 1917, Mt. Slover gained national recognition when Congress gave special permission for a giant American flag to fly continuously from the summit. Slover Mountain and the American flag could be seen off the 10 freeway for many years.
Over time, the mountain’s resources were depleted, which caused the mountain to slowly shrink into the small hill that exists today.
The information in this historical feature was originally part of a video series produced by the Assessor-Recorder-County Clerk’s office.
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