Spanish stone-age cave paintings in Altamira 'under threat' after being re-opened to the public

Tourists observe the drawings in the replica of the cave of Altamira near Santander, northern Spain (EPA)

Just a year after one of Spain’s most important historical sites, the Altamira cave, was reopened to the public, scientists are now saying tourists are causing permanent damage to one of the finest examples of Palaeolithic art anywhere in the world.

A total of 17 academics and 70 researchers from Madrid’s Complutense University have signed an open letter to Unesco arguing that public access to the cave “endangers a fragile legacy of great importance for our understanding of Palaeolithic society”.

Research that suggested strictly limited public access would not damage the cave – which led to the decision by the Spanish culture ministry to reopen – was a mistake, the Madrid-based experts say.

“The action taken by the Spanish culture ministry is a clear threat to its conservation,” the letter reads. “We believe that Unesco and other international organisations dedicated to preserving cultural heritage should take note of the dangers that political decisions pose for the conservation of Altamira.”

Experts believe that the drawings – among the oldest ever found – represent some of the best-preserved examples from the upper Palaeolithic period, which began about 50,000 years ago.

An amateur archaeologist is credited with discovering the cave in 1879, although it has been reported that it was in fact his young daughter who found the drawings of wild animals and human hands while out playing. Using dating techniques, scientists estimate that some of the works are over 36,000 years old.

Public access to the site has always been controversial. In the 1960s and 1970s, experts repeatedly warned that large groups of tourists were damaging the paintings, even by breathing, and public access ended in 1977.

It began again in 1982 with strict controls, which led to a three-year waiting list, and in 2001 a replica of the cave was built for those who could not wait that long.

Altamira was closed to the public again in 2002, but a survey by experts in 2011 concluded that any damage to the drawings caused by tourist access to the cave had already occurred. The culture ministry devised a lottery system, which allowed small groups to visit the site for a little more than half an hour at a time.

Now the cave’s board of trustees must decide whether this decision was flawed. Speaking to the El País newspaper last year, the longstanding director of the cave, José Antonio Lasheras, said: “Management’s mission is to regulate proper conservation and use of the caves and it could be that what was once considered appropriate is no longer so, and vice-versa. I proposed closing the cave in 2002 and take responsibility for the current public visit regime.”