14,400 years ago, five people and a canid entered an Italian cave using pine twigs for light

Imagine yourself in a dark cave, more than 800 meters deep, without a flashlight, GPS, or cellphone to call for help, only a few burning pine twigs to illuminate your way. That’s exactly what a few prehistoric humans did nearly 14,400 years ago in what is now northwestern Italy, and scientists have finally figured out how they did it.

In a new study published in Quaternary International, Daniele Arobba, Rosanna Caramiello and colleagues describe in remarkable detail how a group of five people and their dog made their way deep into Bàsura Cave near Toirano, in the Liguria region, equipped only with small, prepared pine branches for light. The findings challenge a long-standing assumption about how prehistoric people explored the underground world.

The cave that kept its secrets for 70 years
Bàsura Cave, also known as the "Witch's Cave," has fascinated archaeologists since its inner chambers were first entered in 1950. It is one of the most important prehistoric sites in Italy and has a remarkable trail of fossilized human footprints, cave bear remains, charcoal smudges on walls, and even the prints of a canid walking alongside humans.


Early researchers mistakenly identified the footprints as those of Neanderthals, but radiocarbon dating placed the visit much later, in the Epigravettian, near the tail end of the last Ice Age. According to a study by Romano et al. , published in eLife, five individuals of different life stages two adults, an adolescent and two children walked in single file through the cave, apparently led by the largest individual. Published in 2019, the study used laser scanning, photogrammetry and geometric morphometrics to reconstruct the movements of the group in extraordinary detail. The cave had preserved traces of crawling, handprints, and charcoal smears where group members had steadied themselves against the walls.

Reading the landscape from sediment
The researchers had to know the world outside the cave before they could learn about the light. The pollen from the sediments indicated a landscape of open steppe vegetation with scattered pine forests. Plants of cold climates like Artemisia and the daisy family dominated the record. Pine pollen was less abundant, especially that of the Scots pine and its relatives.

Interestingly, most of that pollen hadn’t blown in on the wind. The pollen grains were probably carried on the fur of the cave bears that hibernated in the cave and left huge deposits of bones. The rest was from water seeping in from the outside. It’s a reminder of how interconnected the prehistoric cave ecosystem was human, animal and plant records layered on top of each other.

Torches? Not quite
For years, archaeologists had assumed prehistoric visitors to caves relied on big torches with thick branches, like the ones you might see in a movie. The new research throws that image out the window.

The team’s analysis of charcoal remains in the cave’s Hall of Mysteries found 56 fragments, mostly from Scots pine or close relatives. The key point? The majority were from young branches no more than two or three centimeters in diameter. There were no torches. They were thin branches.

The researchers tested in a nearby cave with environmental conditions similar to those in the field to see if small pine twigs could really do the job. The pine branches were dried and prepared for burning just as prehistoric people would have prepared their fuel. Five people in the original party carried the burning twigs through dark passages.

The results were surprisingly practical. The two twigs burned brightly enough to light the way for all five of them, traveling in single file. If one’s eyes were used to the dark, one could see about ten meters. The little flames gave off little smoke and less glare than larger torches would.

Experiments confirmed that the safest arrangement was one light source in front of the group and one behind. The members in between stayed in touch with each other by putting a hand on the shoulder of the person ahead, a sensible human chain of trust moving through total darkness.

The math of survival
The twigs burned evenly, losing about 4 centimeters in length per minute as they burned. Based on that burn rate, the researchers calculated that the entire round trip from the cave entrance to the Hall of Mysteries and back would have taken about two hours and would have required about twenty twigs, each about thirty centimeters long. A small, manageable package. Nothing complicated.

And the experiments also provided a detail that confirmed the whole picture. The charcoal marks left on cave walls during the tests were very similar to traces already preserved inside Bàsura. Small pieces of charcoal were also accumulating below these wall marks, just as in the archaeological pattern observed in excavations.

Pine was also the dominant tree in the local environment at the time, making suitable branches readily available. The choice of material was not accidental, but practical, informed, and deliberate.

Hints of other visitors
The story does not end with this one group. Elsewhere in the cave, researchers found several pieces of charcoal embedded in a growing speleothem, a mineral formation that builds up over time. Radiocarbon dating shows these samples are from totally different periods than the famous footprint trail. Its origin is unknown, but it suggests other episodes of human presence inside the cave long after the Ice Age group made their journey. Bàsura, it seems, was able to call people back more than once.

A dog in the dark
Perhaps the most surprising and moving detail of all this is the presence of a canid. Footprints suggest that an animal, probably a dog or a wolf-dog, entered the cave with the group. No one can say for sure whether it was a companion, a working animal or just followed the group in out of curiosity. But it gives a curiously human touch to the whole expedition.

This sort of purposeful, inventive behavior is one aspect of the larger story of Upper Paleolithic ingenuity. Experimental work at other Paleolithic cave sites has shown that prehistoric humans selected their lighting materials carefully depending on the context: torches for moving through wide open spaces, fat lamps for stationary work, according to Medina-Alcaide et al. in PLOS ONE. It was never a random decision. In Bàsura, it was the pine twigs, carefully dried, tied in bunches, and taken away in the dark.

Five people, a dog, a bundle of cut pine boughs and the pitch-black interior of a cave thick with the bones of cave bears. What pulled them in there is one of archaeology’s open questions. But we know how they did it at least.