Circle Mountain
El. 6,875Circle Mountain is located just outside of Wrightwood on the San Andreas Fault on the northern side of the San Gabriel Mountains. It has a blend of Montane Tranverse and Mojave plant life. Stands of pinyon pine, flannelbush, mountain mahogany, and lupine populate the slopes. On the summit there are views of the western Mojave, San Gabriel high country, and the distant San Bernardino Mountains. Circle Mountain is located just outside of Wrightwood.
Early use and naming
Circle Mountain takes its name from its broad, rounded form that stands apart from the sharper ridges nearby. Early surveyors along Lone Pine Canyon and the San Andreas Fault zone used the peak as a landmark when plotting out land divisions in the late 19th and early 20th centuries. A U.S. Geological Survey benchmark still sits near the top, reflecting its role in mapping.
Native presence
Before Wrightwood was ever a town, the Serrano people lived throughout the San Gabriel Mountains and Mojave fringe. The Lone Pine Canyon corridor just below Circle Mountain was part of a seasonal travel and trade route connecting the desert floor with mountain villages. Hunters would have used the slopes for vantage points over deer and smaller game.
Logging and ranching days
In the early 1900s, Wrightwood was built up as a ranching community by the Swarthout family. Circle Mountain stood on the eastern edge of their cattle range, and its slopes were cut for timber during the years when sawmills dotted the San Gabriels. Old cut stumps and skid trails can still be found around its lower slopes if you know where to look.
Geological history
Circle Mountain sits directly on the San Andreas Fault, and the Lone Pine Canyon side is essentially a fault trench. The abrupt rise of the mountain has long been used by geologists as a textbook example of how the San Andreas shoves land upward. The 1857 Fort Tejon earthquake, one of California’s largest, is thought to have shifted land in this very area.
When Sumner Wright and his family settled the canyon in the late 1800s, they carved out what became Wrightwood by grazing cattle and raising apples on the broad benches along Sheep Creek. Circle Mountain stood just east of their range. Old-timers in the valley recalled that cattle were sometimes driven up onto its lower slopes to graze during wet springs, when grasses and forbs grew thick before the summer heat. Because Circle Mountain was a rounded, open landmark, it served as a natural boundary point—neighbors would say “cattle east of Circle belong to Wright, west of it belong to Swarthout,” referring to another ranching clan tied into nearby Lone Pine Canyon.
During the 1910s and 20s, when Wrightwood was still a ranching settlement, wood from Circle Mountain’s slopes was cut for fence posts and cabin beams. Ranch hands spoke of the hard work of dragging cut logs down its steep firebreaks with mules. Stories survive of children riding those same slopes in winter, sliding on makeshift sleds fashioned from barrel staves, mixing ranch life with mountain play.
Geological anecdotes
Circle Mountain is a showcase of the San Andreas Fault’s power. It rises abruptly because the fault runs right along its western base in Lone Pine Canyon. Geologists note that the canyon itself is a fault trench, carved when massive earthquakes shifted the earth. The 1857 Fort Tejon earthquake, one of the strongest in California history, ripped the ground for more than 200 miles. Accounts from nearby ranches mention cattle panicking and boulders tumbling off slopes like Circle Mountain when the ground shook.
Later, in the 20th century, geology students from USC and Caltech often came to Lone Pine Canyon because Circle Mountain provided such a clear “textbook” example of a pressure ridge formed by the San Andreas. Professors would point out the way its rounded bulk was literally lifted by fault motion, making it a natural classroom. Local lore says that some students even painted large letters or symbols on rocks near the summit during field trips, though these faded away with weather and time.