Cave of El Castillo

The Cave of El Castillo in Puente Viesgo, Cantabria, was discovered in 1903 by Hermilio Alcalde del Rio. Part of the Caves of Monte Castillo complex, it contains the oldest known dated cave art: a red stippled disk in the Panel de las Manos, uranium-thorium dated to at least 40,800 years ago. The cave holds over 150 catalogued figures including 45 hand stencils, animal depictions of bison, deer, horses, and mammoth, plus abstract symbols. It is a UNESCO World Heritage Site as part of the Cave of Altamira and Paleolithic Cave Art of Northern Spain inscription.