The Sajama Lines of Bolivia are another set of mysterious earth-carvings in South America. First noticed in 1932, the lines are up to ten feet thick, and continue for miles along the ground, often intersecting but never making clear shapes.
The lines cover an area of just under nine thousand square miles, and have been dated to around three thousand years ago. That would suggest that they were made by a tribe who were known to live around the region's volcano during that era. Their meaning is lost to time.