Chauchilla Cemetery in Peru was in operation from about 200 CE to about 1000 CE. Situated in the Sechura Desert near Nazca, the conditions are so dry that those buried in the open-air tombs became mummified. Some even retain their skin and hair! Many have been vandalized by graverobbers over the centuries, but what is left of them still sits in the desert, facing the east, as was the custom. Read more and see plenty of pictures of the mummies of Chauchilla Cemetery at Urban Ghosts.
(Image credit: Colegota)