'Hundreds and hundreds of bones': In a hidden Alpine cave, a mountaineer discovers an Ice Age cave bear graveyard

The BBC reveals images from inside a previously uncharted cave in the Dolomites, containing a trove of skeletons from huge, long-extinct cave bears – offering a rare window into the Ice Age.

Mountain guide Kurt Walde was on a near-vertical slope in the Italian Dolomites, at an altitude of a little over 2,850m (9,350ft), searching for an uncharted cave.

Descending from the mountain summit down a slope littered with loose rock, Walde reached a ledge that he thought would be the cave. It was a false hope.

"At that moment I felt a bit desperate," says Walde. "I continued to downclimb. Eventually, I reached the end of my rope."

Walde was convinced he was close. He hadn't been feeling well that morning, but had donned his 22kg (50lb) backpack anyway. For the last few metres, he dispensed with his rope, and reached the cave's entrance without it.

Inside was an extraordinary sight. Deep in the cave, the glow of his head lamp fell across a graveyard of Ice Age skeletons. They are suspected to belong to Ursus ladinicus, a species of cave bear that went extinct around 24,000 years ago.

Scroll down to see the first images taken inside the cave and sketches of its layout by Walde, shared with the BBC.

The entrance to the newly discovered cave lies across the mountain from another famous site, the Conturines cave, in the Fanes-Senes-Braies Natural Park in northern Italy. So far, that is the only place where Ursus ladinicus remains have been confirmed.

The cave bears found in Conturines weighed around 1,200kg (2,650lb) and were 3m (10ft) long, with males larger than females. Their teeth suggest that they were exclusively plant-eaters, feeding on Alpine herbs, leaves and tougher grasses.

The discovery of Conturines in 1987 transformed what we knew about Ice Age cave bears. Nearly 40 years later, the discovery of this sister cave means our understanding could be set to change once again.

Walde, from the nearby city of Brunico in South Tyrol, has always believed that there is more to Conturines than meets the eye. Walde has been a mountain guide for 41 years, and is one of only two guides to the famous cave.

"During all [those] tours, I always had a feeling that this cave is not all there is to it," says Walde. "I thought there must be something more."

Three and a half years ago, while he was on a peak, Walde spotted a black mark on the mountainside, creating a striking contrast to the lunar-like surroundings.

"That was the first sign," Walde says. Convinced there was something interesting there, he decided one day he would brave the vertiginous slope to get there. "I have to go and see it up close."

In July 2026, Walde finally made up his mind to explore the site, and was met with a treasure trove of ancient remains.

On entering, he was struck by the topographic similarities between this cavern and the Conturines cave.

"I immediately thought this den must be part of a cave system," he says. Ecstatic at having safely entered, "I wanted to extend this moment and feeling as long as possible", he says. He compares it to receiving a gift and wanting to extend the suspense before opening it.

The first 60m (200ft) or so of the cave are a straight line, reaching a large speleothem – a natural mineral deposit – at the end of that stretch. Nearby, he found a solitary bone lying on an elevated bedrock formation resembling a table. The arrangement struck him as "mysterious".

From that point onwards, the cave descends to the left. It was here that Walde came across numerous bones and skulls.

"That was very exciting," says Walde. "I really did my best to control my emotions."

Walde remembers feeling as if he were walking on eggshells to avoid disturbing the findings. He came across what looked like a skull connected to its cervical vertebrae.

It dawned on him that this was once a place "full of life" and activity, so long ago. "That was the strongest sensation."

This den and its neighbour, Conturines Cave, is found in the Fanes-Senes-Braies Natural Park in northern Italy. 

Some of the bones in Conturines were those of the common cave bear. Others were eventually found to belong to the previously unknown Ursus ladinicus, named in honour of the Ladin community who live in the mountains where it was found.

Research suggests that the bones found there date to at least 46,000 to 50,000 years old. The cave is also climate time capsule, thanks to certain mineral deposits it holds, some of which are six million years old.

The Dolomites could have been warmer than the current average temperature when the bears existed, research from the cave suggests, and the beech tree line may have been at a higher altitude compared to present day – potentially providing food for the bears.

The Conturines bones showed these cave bears were not alone. The discovery of a cave lion jawbone and a separate tooth were found in the cave. The remains of cave hyenas, lions and leopards have also been found in other alpine caves that date from the same era as the cave bears. 

One of the first people to be notified of Walde's discovery was Christian Terzer, director of the Province of Bolzano's Department of Archaeology. Terzer had only taken the post in early August. When he found out about the discovery as he began the job, it became something of a baptism of fire.

Terzer tells the BBC that it was only after discussing the discovery with local palaeontologists that he realised its significance. Thoughts of potential contamination of the site began to trouble him. "I also had some sleepless nights."

To prevent trespassing, the department erected a gate some 20m (66ft) inside the opening, with an additional tarpaulin further in to seal off this crucial evidence. The material had to be airlifted to the highly inaccessible cave, which was no easy feat.

"I was impressed with the number of bones," says Terzer, who visited the site in early autumn. "There are hundreds and hundreds of bones there. I don't know how many individual bears are inside, but it's quite a lot."

Terzer is also quite sure that "in this new cave there are far more specimens than in the Conturines Cave". 

The solitary bone on the stone table that Walde had noticed was also one of several unusually placed bones that caught Terzer's attention.

"It's strange that some isolated bones are placed on big rocks," says Terzer. "We will have to find out how [they ended up there]. Maybe through a natural process, or maybe there were humans inside thousands of years ago."

While winter provides Terzer and his team with a break from exploration, scientists can concentrate on the project to come. He and experts in the field intend to resume scientific work inside the cave from June 2027.

Martina Pacher is well acquainted with the Conturines Cave. She is a vertebrate palaeontologist at the Natural History Museum of St Gallen, working mainly on cave bears and ice age fauna, and took part in excavations at the 1987 landmark as a student.

Pacher recalls feeling awed when she got the news of the newly discovered cave. For her, the find now raises various questions.

First, how did the bears access the cave. The cave's mouth as it appears now is highly inaccessible, but the cave must once have been accessible to bears. There must have been no ice blocking it and temperatures would have to have been suitable for the bears, Pacher says.

Currently, there is no visible connection between the newly discovered cave and the 1987 cave. But this may not always have been the case.

"The old Conturines Cave and this new one may probably be connected somehow, but we're not sure yet," she says.

Over millennia, the entrance to the cave may have changed, she says, but it's too early to tell how or by how much.

Pacher also hopes the discovery could help answer the question of what the bears looked like. "If we find many more-or-less complete skeletons we have much better possibilities to reconstruct the appearance of these bears," she says.

"We may find more skeletons beneath the sediments or at least bones that we can rearticulate later," Pacher says. "Then we might understand better about the family ties and social behaviour of these animals."

Indeed, these findings are a window to past ecosystems and environments that are completely different from today, says Spyridoula Pappa, a senior curator of fossil mammals at London's Natural History Museum who has worked on teeth from the Conturines Cave.

"What excites me about this is the possibility of studying a much more complete assemblage [of bones]," says Pappa. She hopes it will allow scientists to extract evidence from teeth, skeletons, genetic material and geological context to build a much fuller picture of these "remarkable alpine bears".

She wonders what else may be found in the cave. "We also need to see if they're all cave bear remains," says Pappa.

For Pacher, the most important objective for now is to preserve the site as best as possible, as preventing disturbance holds the key to understanding this treasure trove of bones. Walde, too, hopes one day to return to the cave, perhaps in 10 years' time, to find it in the same condition as he found it.

For now, the cave remains sealed and barred, to prevent unauthorised access before Terzer's team returns in 2027.

More like this:

• Giant eagles once ruled the skies, snatched human children, and shaped our evolution

• The whale graveyards that transform the deep sea

• The blood-curdling Permian monsters that ruled the Earth before dinosaurs

The research that will be carried out here could answer questions both big and small.

It could shape our understanding of the animals that roamed the Dolomites and the Alps in the distant past. It could reveal how the bears once accessed this now highly inaccessible cave. And it could even explain curiosities like how a solitary bone found itself positioned on its table-like stone.

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