About 500 rock circles have been found in California’s Anza-Borrego Desert State Park. In less than 10 square miles of the park’s grounds, these ancient rings dot the landscape and no one is sure why.
Experts are having a hard time nailing down the age of the rocks themselves. What we do know is these didn’t form by themselves. In a phone interview with FOX5SanDiego, associate state archaeologist in Southern California Hayley Elsken said “There’s no way the rock line circles are naturally occurring.”
Another weird thing is how concentrated just this one area is with them. Archaeologist Malcolm J. Rogers, who worked all over Southern California in the early 20th century, also noticed thousands of similar rock circles in other state deserts. And the ones he documented don’t stay a consistent size, they can be anywhere form 5 to 12 feet.

All of them are made of neatly arranged rocks in a cleared-off area. Which certainly makes them stick out against the otherwise rocky landscape. And when we say clear, we mean cleared. Archeologists are finding very few artifacts near the circles themselves. When normally sites of places like ancient villages can yield 1000s of artifacts. Even if these areas had a more temporary purpose there should be more common items like pottery or food processing. But so far they have only found a handful of small tools in these areas.
While we still aren’t sure who made these rock circles, some experts attribute them to Native Americans. Since Anza-Borrego is the traditional homelands of the Cahuilla, Kumeyaay, and Cupeño, Elsken points out.

While there is no clear reason anyone can find for these to be made, there are a few popular theories. Rogers noted that they may be “sleeping circles,” which were used by early hunters to sleep for the night. Elsken adds that one person could probably fit snugly in each circle.
It’s also possible these were used for something like meditation since they are often on elevated surfaces, allowing for a nicer view. But no matter what their original purpose was these rock circles currently serve as a reminder of the land’s rich history. “This is the Kumeyaay land and we’re guests on it,” Elsken says. “Respect that land, especially when we see cultural sites.”