Axlor cave

Axlor is a rock shelter and cave site in Dima, a small municipality in the Basque Country of northern Spain, recognized as one of the most important Middle Paleolithic sites on the entire Iberian Peninsula. The site sits on the slope of Mount Urrestei, in an area known as Kobalde-Indusi, right beside the natural rock arch called Jentilzubi, roughly fifteen meters above the ravine that drops toward the Indusi gorge.

How was Axlor discovered?

The shelter was found in 1932 by Basque ethnographer and prehistorian José Miguel de Barandiarán, while he was carrying out work at the nearby Baltzola cave. Systematic excavations at Axlor itself did not begin until 1967 and continued through 1974, spanning eight field seasons under his direction. Later research campaigns led by university teams have returned to the site in subsequent decades, uncovering further human and animal remains and refining the site's chronology.

What has been found inside the cave?

Axlor belongs to the Mousterian culture and is tied to Neanderthal occupation spanning roughly 100,000 to 50,000 years ago. The oldest deposits, labeled levels N through F, formed around 100,000 to 80,000 years ago, level D dates to about 70,000 years, and level B to roughly 50,000 years.

Excavators recovered an extensive stone tool assemblage, including characteristic Mousterian sidescrapers made from flint transported from distant sources — evidence that Neanderthal groups moved across the landscape and maintained networks for exchanging raw materials. Researchers identified different knapping techniques through the sequence: a microLevallois approach in the lower levels and a distinctive Quina-type technique in level D. The site has also yielded more than a thousand bone tools, mostly retouchers made from long-bone shaft fragments, among the richest such collections in the region.

One particularly striking find is a stone bearing an engraved X-shaped mark, dated to at least 45,000 years old — cited as evidence that Neanderthals were capable of symbolic, graphic behavior independent of the later arrival of modern humans in Europe. The cave has also produced human remains, including teeth and a skull parietal fragment, showing morphological features consistent with Neanderthals, while analysis of bird and carnivore bones from the Mousterian layers revealed cut marks left by human processing — documenting a diet that extended beyond typical large-game hunting.

Why does Axlor matter to researchers?

The site preserves one of the most complete Middle Paleolithic sequences in the North Atlantic region of the Iberian Peninsula. Studying its successive occupation layers has let scientists trace how Neanderthal groups organized their lives seasonally and adapted to a shifting Atlantic forest environment across tens of thousands of years, moving between warmer interglacial phases and colder glacial ones.

How do you get to Axlor?

Dima lies inland in Biscay, about 30 kilometers from Bilbao, tucked among the hills and valleys typical of the Basque interior. A car is the most practical way to reach the area — local roads lead toward Mount Urrestei, from where the shelter itself is reached on foot along a mountain trail. It's worth knowing that Axlor remains an active research site rather than a cave adapted for visitors, so access to the interior can be restricted; the main draw for travelers is the surrounding landscape and its deep historical context.

What else is worth seeing nearby?

The same municipality holds the Baltzola cave, where Barandiarán was excavating at the very moment he discovered Axlor, and which is known for its own Paleolithic cave art. Dima and its surrounding hills also make a good base for hiking through Biscay's green valleys, past pastures and beech woodland typical of the Basque countryside.

When is the best time to visit?

Spring and early autumn bring the most comfortable conditions, with moderate temperatures and dry, passable mountain trails. Summer can turn hot in direct sun, though the green valleys of Biscay temper the heat, while winter brings frequent rain and fog that can make the approach to the site more difficult.

Frequently asked questions

Can you tour Axlor cave like a typical show cave? No — it remains an active archaeological research site rather than a commercially developed cave, so access can be limited depending on ongoing or periodic fieldwork.

Who lived in Axlor cave? Neanderthal groups associated with the Mousterian culture, occupying the site at different points between roughly 100,000 and 50,000 years ago.

What is the most significant discovery from Axlor? Alongside its rich stone and bone tool collections, the stone engraved with an X-shaped mark stands out, seen as evidence of symbolic behavior among Neanderthals.

How do you get to Dima? The easiest way is by car from Bilbao, about 30 kilometers away — the drive typically takes under an hour depending on traffic and time of day.