The drawings at this UNESCO World Heritage site date back to the Palaeolithic age making them some of the earliest known artworks known to man. Spanning throughout 17 different caves, the drawings depict wild animals like bison and deer and human hands. It might be expected that after 20,000 years, the usual wear and tear would begin to effect the quality of the paintings. In 2002, the Spanish government closed the site to the general public. Today, the nearby museum draws big crowds, and once a week, five lucky visitors are chosen at random to don protective gear and visit a selected area of the cave for 37 minutes