Cartailhac’s famous retraction of his opposition to the concept of paleolithic cave wall art, published over 20 years after Sanz de Sautuola’s discovery of the Altamira cave paintings in northern Spain. Cartailhac, one of the most influential prehistorians of the time, had ridiculed Sanz de Sautuola’s announcement of the Altamira paintings at the 1880 Prehistorical Conference in Lisbon; his refusal to accept the paintings’ authenticity—or even to visit the Altamira site—retarded the study of cave art for two decades. The case against paleolithic cave art was weakened by the subsequent discovery of several examples in France, including La Mouthe, and in 1902 Cartailhac finally agreed to go to Altamira to see the cave’s paintings for himself. Convinced by this visit, Cartailhac became one of the most fervent and enthusiastic scholars of cave art, publishing several works on the subject.