Could it be ancient aliens? Standing in front of the perfectly carved stone spheres near Sierpe, you might just find yourself wondering. These mysterious orbs have baffled scientists, archaeologists, and, yes, even the producers of Ancient Aliens, who featured Costa Rica’s stone spheres in an episode all about unexplained artifacts.
Scattered across the Diquís Delta and found in clusters throughout the southern Pacific region, these stone spheres range from the size of a soccer ball to massive boulders weighing several tons. No one knows exactly who carved them, how they managed such precision without modern tools, or what purpose they served. Were they celestial markers? Symbols of power? A giant prehistoric bowling alley? Or—cue the spooky music—messages from extraterrestrial visitors?
What we do know is that the spheres were shaped by an ancient civilization, likely the Diquís culture, sometime between 500 and 1500 AD. They carved the spheres from granodiorite, a hard igneous rock found in the region, and somehow transported them across miles of jungle. Many theories have been proposed: they may have marked important ceremonial sites, indicated status, or even been placed in alignment with astronomical events. But despite decades of study, the true meaning behind the spheres remains a mystery.
If you’re making your way to Casa Roja, you’ll pass right by some of these enigmatic stones. There’s an excellent collection at the Finca 6 museum, just off the road to Sierpe, where you can see the spheres in their original archaeological context. And in downtown Sierpe, you’ll spot some more right in the town square. These are replicas (we’re sorry to say), but they still give you a great sense of the craftsmanship and scale.
Whether you believe they’re evidence of ancient alien contact or simply a stunning achievement of human ingenuity, the stone spheres of Sierpe are one of Costa Rica’s most intriguing mysteries. So next time you’re gazing up at the stars from Casa Roja, don’t be surprised if you find yourself wondering… are we really alone?
