Red dots, hand stencils and animal figures represent the oldest examples yet found of cave art in Europe.
The symbols on the walls at 11 Spanish locations, including the World Heritage sites of Altamira, El Castillo and Tito Bustillo have long been recognised for their antiquity.
But researchers have now used refined dating techniques to get a more accurate determination of their ages.
One motif - a large red dot - is said to be more than 40,000 years old.
keyboard shortcuts: V vote up article J next comment K previous comment