Ica stones are considered by some people to be proof that there was once a technologically advanced civilization on Earth. They were reportedly discovered in a cave of unknown location near the city of Ica in Peru and popularized by Peruvian physician Javier Cabrera. Scientific testing of the more than fifteen thousand stones dates them as being from prehistoric times, but the stones are carved with images of things that would have been unfamiliar to any known prehistoric people. Contradicting both existing knowledge of Peruvian prehistory and evolution, they are considered prime examples of out-of-place artifacts.
The stones are composed of andesite and vary in size from pebbles to boulders. They are shallowly engraved through their surface patina with a variety of images, purportedly depicting a variety of phenomena: For example, some of the stones seem to depict surgical equipment, blood transfusions, cesarean sections, and life support systems, as well as men using a telescope, Incan or Aztec men riding and attacking dinosaurs, extinct animals, flying machines, bestiality, star and land maps.
Interestingly, the cave where the farmer claimed to have found the stones is near an area of mysterious lines scratched into the ground, the Nazca lines, which some people claim was once a landing site for extraterrestrial spacecraft. Cabrera thinks that this is the site from which Gliptolithic man left Earth. He further believes, based on some of the celestial drawings on the stones, that the Gliptolithics headed for a planet in the Pleiades star cluster.