The Colby Mammoth Site

Ice Age Giants Buried in the Wyoming Badlands

Just north of Worland, Wyoming, in the heart of the Bighorn Basin, lies one of North America’s most significant Ice Age paleontological sites, the Colby Mammoth Site. Though quiet and unassuming from the surface, this patch of Wyoming soil once held the bones of giant creatures and clues to the humans who may have hunted them. Today, it stands as a fascinating window into a world 20,000 years gone, when mammoths roamed the region and ancient hunters stalked them across the plains.

For anyone interested in prehistory, paleontology, or Wyoming’s deep past, the Colby site is a powerful reminder of how much story lies just beneath our feet.

A Discovery in the Dust

The site was first discovered in 1962, when rancher Bill Colby unearthed large bones while digging on his property. Initial examination revealed mammoth remains, and by the late 1970s, a formal excavation was underway led by renowned paleontologist Dr. George Frison and a team from the University of Wyoming.

What they found was remarkable: the remains of at least five Columbian mammoths (some of the largest land mammals to ever walk North America), along with stone tools, strong evidence that early humans had interacted with, and possibly hunted, these enormous creatures. Radiocarbon dating placed the site at roughly 11,000 to 13,000 years old, placing it firmly within the Late Pleistocene epoch and aligning it with the Clovis culture, one of the earliest known human groups in North America.

Mammoths and the Clovis People

The Columbian mammoth stood up to 14 feet tall at the shoulder and weighed as much as 10 tons. Unlike their woolly cousins of the far north, Columbian mammoths were built for the open grasslands and more temperate climates of the American West.

The discovery of Clovis-style spear points among the bones at Colby helped strengthen the theory that these early people were capable of bringing down such massive game using finely crafted tools of stone, skill, and teamwork. The site remains one of only a handful in the country that clearly links Pleistocene megafauna to early human hunters.

Visiting the Site Today

While the original excavation area has since been backfilled to protect its contents, the legacy of the Colby Mammoth Site lives on in nearby Worland at the Washakie Museum & Cultural Center. Here, you can view cast replicas of mammoth bones, original tools, and detailed exhibits explaining the significance of the site and its broader context in Ice Age history.

Interpretive signs at the actual site (located on private land) tell the story of the discovery and excavation, and the views across the Bighorn Basin allow visitors to imagine what the landscape might have looked like thousands of years ago, herds of mammoths, sabertooth cats, early humans moving across an open and untamed land.

A Place Where Time Runs Deep

The Colby Mammoth Site is not a major tourist destination, and that’s part of what makes it so compelling. It’s a quiet, humble patch of ground that once held giants. A place where the lines between natural history and human story blur. A reminder that long before roads and ranches, this land echoed with the heavy steps of mammoths and the sharp eyes of hunters tracking them.

If you’re traveling through Worland or the southern Bighorn Basin, take time to visit the museum and drive out to the site. It’s not flashy — but it is profound. And it might just shift the way you think about the land beneath your feet.