Lauded as the first place in the world where the cave markings of pre-civilization were discovered, this cave near the northern coast of Spain boasts many Paleolithic interpretations of animals and natural phenomenon. The disappointment here is that the cave has been closed to the public so it may be better preserved, so your next best option is to go to the Altamira Museum, which houses a replica cave and related artifacts. A must see for adventurers with archeological or anthropological interests!
Note:The museum is located just outside of Santillana del Mar, a small Cantabrian town. For those who need the real thing, there are a number of caves within a few hours that also contain prehistoric cave paintings, including the Cave of Chuffin in Rionansa, the Caves del Monte Castillo in the town of Puente Viesgo and the Basque cave of Santimamiñe.