For 12 years, visitors wanting to see Spain's prized prehistoric Altamira cave paintings have had to settle for a replica in a museum a few hundred feet away. But from Thursday, small groups of visitors will again be allowed in the cave, which has been described as the Sistine Chapel of paleolithic art, as part of an experiment to determine whether the paintings can support the presence of sightseers. The vast cavern complex, in the Cantabria region of northern Spain , was made a World Heritage Site by Unesco in It is covered in paintings dated to between 14, and 20, years ago of animals including European bison and bulls.
From now until August, on a randomly selected day of the week, visitors to the replica cave in the Museo de Altamira will be invited to enter a draw; five will be chosen to take a guided tour including 37 minutes inside the cave.
Visitors will have to put on special suits, masks and shoes before entering the site. Up to lucky winners are expected to visit the cave in total. While they admire the red and black paintings on the limestone walls, researchers will measure their impact on the cave's temperature, humidity, microbiological contamination and CO2 levels.
The results will be used to determine whether or not the cave can be reopened to the public, a controversial decision that has pitted the local tourist economy against government scientists.
The site has been closed several times, starting in after scientists warned that body heat and CO2 levels from the 3, daily visitors were deteriorating the paintings.
