Tourists Have Been Visiting this European Site for over 40,000 Years

(CNN) - European tourism is as old as time. In the 19th century, the US glitterati would pop over to Paris to refresh their wardrobes. From the 1700s, places like Venice and Rome were becoming essential tourist stops in Italy. In the Classical era there were, famously, the seven wonders of the world.

None of these compare, however, to a cave in southern Spain which – it has just been revealed – has been visited by humans for over 41,000 years.

The Cueva de Nerja, or Nerja Caves, are a three-mile series of caves near Nerja in Malaga province, southern Spain. Now famed for their dramatic stalactites and stalagmites, they were “discovered” for the first time in thousands of years in 1959 by five friends out looking for bats. Today, visitors can take a 45-minute tour of the “public gallery” to see fantastical formations of stalactites, stalagmites and other speleothems – shapes and structures caused by mineral deposits.

But thousands of years ago, visits took place for more spiritual reasons. So far, 589 prehistoric paintings have been discovered in the caves (modern visitors cannot visit those areas for conservation reasons). The spaces were also used for funerary rites.

In a new study for the journal Scientific Reports, researchers from the University of Cordoba have established that visits to the caves go back much further than expected – and that the Cueva de Nerja “hosted” the most prehistoric visits of any European cave with Paleolithic art.

Researchers found evidence of visits dating back to 41,218 cal. BP – or 41,291 years prior to today. The date is 10,000 years earlier than previously thought.

The authors wrote in the study that traditionally, when studying prehistoric activity in caves, “it is difficult to determine if remains [such as rock art, fire remains or human constructions] were left by single visits or recurrent ones.”

However in Nerja, they were able to use carbon dating to work out the age of soot stains on the walls and charcoal on the ground – left by the fires, fixed ‘“lamps” and, most importantly, torches that visitors used to illuminate their way. The specks of charcoal from flaming torches scattered throughout the chambers – like the breadcrumbs in the story of “Hansel and Gretel,” wrote the authors – were able to be dated.

The “smoke archaeology” produced 68 radiocarbon samples, of which 53 were able to be dated. They were then cross-referenced with soot microlayers in a stalagmite, and researchers also looked at charcoal particles from pigment used on the walls. In one “room” of the cave, no fewer than 66 samples were taken.

The process has identified “35,000 years of human occupation in the deep karst” and “at least 73 phases of distinct visits… between the Upper Palaeolithic and Recent Prehistory,” wrote the authors. That is the largest number of visits known for any prehistoric cave in Europe. They also found evidence of visitors from prehistoric cultures which had previously been thought to have left little trace in southern Spain.

Meanwhile, analysis of soot “microlayers” enabled the scientists to investigate the final three visitation phases – from roughly 8,000 BCE to 3,000 BCE – finding that there were “at least 64 distinct incursions, with an average of one visit every 35 years for the Neolithic period,” main author Marián Medina told CNN via email.

The “Lower Galleries” of the cave were the most visited – coincidentally, that’s closest to where the modern tours take place. Prehistoric visitors mostly burned one type of pine to light their way, the carbon analysis revealed.