Marcelino Sanz de Sautuola y de la Pedrueca accidentally discovered Paleolithic paintings in 1868 with the help of a hunter named Modesto Cubillas in Altamira's caves, northern Spain.
Altamira
"The captivating true story of Marcelino Sanz de Sautuola, a Spanish nobleman who stumbles upon a groundbreaking discovery in the Altamira caves, revolutionizing our understanding of prehistoric human history."