At Abric Romaní, a rock shelter near Barcelona, charcoal fragments are mapping out how Neanderthals used space around their fires tens of thousands of years ago. The tiny remains suggest that firewood and ash did not simply scatter at random: their concentrations differ between the northern and southern parts of one camp layer.
The shelter preserves traces of Neanderthal life from levels dated between 110,000 and 40,000 years ago. In the layer examined, called Ra, researchers have identified an inner area linked to hearth activities and outer areas associated with toolmaking. Hearths offered warmth and a place to cook, but they also shaped the daily work of a camp. Where people gathered, burned fuel and moved the remains could leave clues long after the fire went cold.
Researchers hand-collected charcoal from the Ra layer during excavations from 2019 to 2022. They examined the fragments under a microscope to identify the wood and look for signs of growth, decay, burning and mineral deposits. They then mapped charcoal concentrations and used statistical tests to compare patterns across the site.
The team analyzed 640 fragments. About 76% came from mountain pine, matching earlier findings that this readily available tree supplied most of the fuel. Signs of wood growth and decay point to people gathering mostly deadwood, likely including fallen branches collected nearby.
The charcoal’s location revealed two distinct patterns. In the north, a broad concentration lay close to hearths. The researchers interpret this area as a primary place where fire-related waste accumulated. In the south, smaller, isolated clusters appeared, often away from hearths. These may be remains moved during hearth cleaning, making the southern area a possible secondary deposit.
That explanation is not certain. The southern clusters could reflect people moving ash and charcoal, differences in how remains survived, or both. Southern fragments also showed more mineral deposits and fungal traces, which may relate to water moving through the shelter. Such traces can have more than one cause, and the study cannot tell whether the layer records one long stay or several visits separated by time away.
The findings add a new kind of evidence to a site often studied through bones and stone tools. Charcoal maps can help researchers ask how people managed fires and organized living areas, but they work best alongside other clues. Bones, tools and microscopic sediment may help test whether people cleaned hearths; matching broken artifacts and tiny debris could help reveal whether the shelter saw one occupation or several.
For now, the charcoal offers a careful glimpse rather than a complete floor plan. As researchers compare it with other evidence from Abric Romaní, the small fragments may help show how Neanderthals handled the everyday tasks that kept a camp functioning.