There’s a hidden hiking spot next to a popular SoCal hiking trail in San Diego that most people walk right past without knowing it’s actually an ancient volcano.
Mount Calavera—found in the Calavera Nature Preserve in Carlsbad—might seem like an ordinary hill, but it was formed by powerful geologic forces millions of years ago, according to NBC San Diego.
Even longtime residents of the quiet neighborhood are often unaware of the ancient secret among them.
Hiker Channin Franz told NBC 7 she only learned the truth after her husband pointed it out, admitting she “didn’t really believe him at first” until reading the information on-site.
The volcano dates back roughly 22 million years, created when the North American and Pacific plates collided in a process called subduction.
Today, what stands is a “plug dome volcano.” Visitors are greeted by the volcano’s exposed “throat,” where hexagonal rock columns reveal the artistry of cooling magma.
“Where you see all those hexagonal columns…that was the throat of the volcano,” geologist Dr. Pat Abbott explained to NBC.
“At its time, the magma was coming up, pushed by gas, the gas was blasting pieces into the air, until the gases were mainly exhausted,” Abbot said.
Though its past was explosive, the site poses no threat today as it remains dormant.
“Dormant is when we still see magma below the surface, still see a lot of little earthquakes…this here, there is no magma, there are no little earthquakes here. This volcano is extinct. It will never erupt again, not even during a large earthquake.”
Now, instead of lava flows, the preserve draws hikers, bikers, and families with scenic views, including a roughly 1.9-mile loop around the lake and miles of trails.
“I like how it’s really big,” 7-year-old resident Samuel Franz told the outlet.
Spanning over 100 acres, the area has become one of North County’s most unusual outdoor escapes, where visitors can literally walk through the remains of a volcano without realizing it.