This is the world's largest preserved effigy mound. Serpent Mound in Ohio resembles a giant snake with a head and a curled tail. Its body is 411 meters / 1348 feet long and has seven coils. Carbon dating suggests that the people of the Adena Culture were the original builders of the Serpent Mound around 300 BC.
Some native cultures in North and Central America recognized snakes as possessing supernatural power. This is probably why the Serpent Mound may have had a religious purpose. The burial mounds nearby indicate that the area served an important mortuary function.
