Nebraska has a Pompeii — and it’s full of ancient rhinos frozen in volcanic ash

It’s the Great Plains’ best-kept fossil secret

Twelve million years ago, a supervolcano in present-day Idaho sent a wall of ash nearly 1,000 miles east across the Great Plains.

It buried an entire watering hole in what is now northeast Nebraska, killing everything that drank there.

Today, you can stand inside a 17,500-square-foot barn and look down at those same skeletons, still lying exactly where the animals fell.

Paleontologists work right in front of you, brushing ash off bones that haven’t seen daylight in 12 million years. The story of how this place came to be starts with one very bad day on the ancient savanna.

A supervolcano 1,000 miles away buried the plains in ash

About 12 million years ago, a supervolcano erupted in what is now southwestern Idaho. That same volcanic system still sits beneath Yellowstone National Park today.

The eruption launched a massive cloud of ash that drifted east and blanketed the Great Plains.

About a foot of it covered the landscape, but at a low-lying watering hole in present-day Antelope County, ash piled up eight to 10 feet deep.

Back then, this part of Nebraska looked nothing like it does now. It was a broad, warm savanna full of animals that no longer exist in North America.

Birds died first, then horses, then the rhinos

The watering hole was likely the only water source for at least a mile in any direction, so animals kept coming back even as the ash fell.

Birds and turtles went first, probably within hours, because their lungs couldn’t handle it. Smaller animals like three-toed horses, small deer and camels hung on a little longer but eventually dropped.

The barrel-bodied rhinos, the biggest of the bunch, lasted the longest before the glassy ash filled their lungs and slowly suffocated them.

Every skeleton at the site shows signs of Marie’s Disease, a bone condition caused by severe lung damage.

A baby rhino skull poking out of a cornfield started it all

In 1971, paleontologist Michael Voorhies from the University of Nebraska State Museum spotted something unusual. A baby rhino skull was eroding out of a gully at the edge of a cornfield.

When he started digging, he found the skull connected to a complete skeleton, and more skeletons surrounded it.

Full excavations in the late 1970s pulled nearly 100 complete rhinos from the ground, along with dozens of horses, camels, turtles and cranes.

The Nebraska Game and Parks Foundation bought the land in 1986, and the park opened to the public in 1991.

Walk above 12 million-year-old skeletons in the Rhino Barn

The Hubbard Rhino Barn opened in 2009 and covers 17,500 square feet of the active dig site. Climate control inside the building protects the fossils while paleontologists keep excavating.

You walk along specially built walkways and look straight down at skeletons still embedded in volcanic ash. A balcony on the upper level gives you an overview of the entire bone bed.

Illustrations of the ancient creatures line the walls, showing what they may have looked like when they were alive. The staff working below will happily answer your questions about what they’re uncovering.

These rhinos looked more like hippos than anything alive today

The barrel-bodied rhino, Teleoceras major, is the most common animal at the site, with more than 100 skeletons found so far.

They stood about three and a half feet tall at the shoulder with short legs and barrel-shaped bodies, looking more like modern hippos than today’s rhinos.

Both males and females had a single small horn on the nose, though males carried larger tusks. One female was preserved still carrying her unborn calf.

Some rhinos were found in what appear to be mother-and-baby pairs, with young rhinos in nursing position beside adult females.

Five species of ancient horses and a giraffe-like camel

Horses come in five different species at this site, including both three-toed and one-toed varieties. Three species of camels roamed the area too, and one of them stood tall and thin like a giraffe.

Among the other mammals found here are a saber-toothed deer, fox-sized dogs and a raccoon-like dog. About 40 crane skeletons have turned up, some still with preserved feathers and gut contents.

Three species of turtles made the list, including a giant land tortoise with a shell four feet long.

Some still had their last meal in their mouths

What makes this site different from most fossil beds is that these skeletons are whole and lying in lifelike positions. At most sites, you find scattered bones that piled up over thousands of years.

Here, many animals still have their bones connected in the correct order, preserved in three dimensions. Some still had the remains of their last meals in their mouths or stomachs, including grass fragments.

The quick burial in ash, combined with minerals from groundwater, created some of the best-preserved fossils ever found.

Scientists have studied details rarely available from ancient animals, like diet, social behavior and population makeup.

Start at the visitor center’s fossil prep lab

Every visit begins at the visitor center, where interpretive displays walk you through the site’s history and science.

Through a glass window, you can watch researchers in a working fossil preparation lab as they clean and preserve specimens. The paleontologists welcome questions about their work.

Hands-on displays let you and your family step into the role of researcher and learn how fossils reveal clues about the past. The park also runs educational programs on a regular basis.

Bronze rhinos guard the trail to the dig site

A paved path leads from the visitor center to the Rhino Barn through grasslands and wildflowers.

Along the way, a geologic timeline trail uses markers to walk you backward through millions of years of Earth’s history.

Life-size bronze sculptures of two battling rhinos and an ancient tortoise stand along the landscape, created by artist Gary Staab.

The Theodore F. and Claire M. Hubbard Family Foundation funded the sculptures to help you picture the creatures that once roamed here.

Exposed dig areas along the path hint at the fossil riches still buried beneath the surface.

A mile-long trail through rolling prairie and wildflowers

The park has a mile-long interpretive hiking trail through rolling grassy hills in the Verdigre Creek valley. Signs along the way help you identify local plants and wildlife.

The landscape runs through mid-grass and tall-grass prairie, which pulls in birds, butterflies and other wildlife throughout the season. You can explore the geology, plants and animals of the area at your own pace.

When you’re ready for a break, a covered picnic shelter and tables let you sit down for a meal surrounded by Nebraska countryside.

New fossils keep turning up every summer

Ashfall is not just a place to look at old bones. It’s a working research site where new fossils come out of the ground each summer.

Student paleontologists and university researchers carry out the excavation work, gaining hands-on experience in the field. Modern tools like CT scanning now let them study fragile bones without disturbing them.

Recent research on fossilized rhino teeth showed the animals likely lived near the watering hole year-round instead of migrating.

Much of the fossil bed remains unexcavated, so future visitors may watch a discovery happen right in front of them.

Explore Ashfall Fossil Beds in Nebraska

You’ll find Ashfall Fossil Beds State Historical Park at 86930 517 Ave, Royal, Neb., about six miles north of U.S. Highway 20.

The park is open seasonally from May through mid-October, so plan your trip for summer or early fall.

Admission runs $8 per person for ages 3 and up, and you’ll also need a Nebraska park entry permit for your vehicle, which you can buy in advance on the official website.

Most visitors spend one to two hours exploring the visitor center, Rhino Barn and trails.

This article was created with AI assistance and human editing.

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