It is renowned for prehistoric cave art featuring charcoal drawings and polychrome paintings of contemporary local fauna and human hands.

The controversy continued until 1902, by which time reports of similar findings of prehistoric paintings in the Franco-Cantabrian region had accumulated and the evidence could no longer be rejected.

Human occupants of the site were well-positioned to take advantage of the rich wildlife that grazed in the valleys of the surrounding mountains as well as the marine life available in nearby coastal areas.

Around 13,000 years ago a rockfall sealed the cave's entrance, preserving its contents until its eventual discovery, which occurred after a nearby tree fell and disturbed the fallen rocks.

In 1879, following its discovery a decade earlier, amateur archaeologist Marcelino Sanz de Sautuola was led by his eight-year-old daughter María to the cave and realized that the markings on the walls constituted drawings.

[7] The cave was excavated by Sautuola and archaeologist Juan Vilanova y Piera from the University of Madrid, resulting in a much acclaimed publication in 1880 which interpreted the paintings as Paleolithic in origin.

The French specialists, led by Gabriel de Mortillet and Émile Cartailhac, were particularly adamant in rejecting the hypothesis of Sautuola and Piera, whose findings were loudly ridiculed at the 1880 Prehistorical Congress in Lisbon.

Due to the high artistic quality, and the exceptional state of conservation of the paintings, Sautuola was accused of forgery, as he was unable to answer why there were no soot (smoke) marks on the walls and ceilings of the cave.

The oldest sign found, a "large red claviform-like symbol of Techo de los Polícromos", was dated to 36.16±0.61 ka (corrected), i.e. still well within the Aurignacian.

A red dotted outline horse, also in the Techo de los Polícromos chamber, was dated to 22.11±0.13 ka (beginning Solutrean), establishing that the paintings span a period of more than 10,000 years.

The comic series depicts the adventures of a group of prehistoric cavemen, shown as modern people, but dressed in pieces of fur, similarly to the Flintstones.

The song "The Caves of Altamira" appears on the 1976 album The Royal Scam by jazz-rock band Steely Dan, later covered by soul group Perri.

The mid-20th-century modern dinnerware line Primitive, designed by Viktor Schreckengost for the American pottery company Salem China, was based on the bison, deer, and stick figure hunters depicted in the Altamira cave paintings.