In 1903, in this 16th-century hamlet in the Pas Valley, four caves were discovered under the 1,150-foot peak of Monte del Castillo, two of which—Cueva del Castillo and Cueva de las Monedas—are open to the public. Bison, deer, bulls, and humanoid stick figures are depicted within the caves; the oldest designs are thought to be 35,000 years old. Most arresting are the paintings of 44 hands (curiously, 35 of them left), reaching out through time. The painters are thought to have blown red pigment around their hands through a hollow bone, leaving the negative image. Reservations are essential.
Mt. del Castillo, Puente Viesgo, Cantabria, 39670, Spain