Fact: Fifteen circles, forming an Earth grid, connect all major ancient sites.
Controversy: Who really built the sites, and why?
Some people contend that aliens assisted the ancient people with the building and location of the sites, perhaps to harness the Earth's increased magnetic energy in these areas. Other people hold the belief that ancient people were much more advanced, and knew secrets of technology that are lost to us today.
Regardless of which side you take, or if you have your own theory, how totally cool is it that the Earth has a natural magnetic grid marked by ancient sites?
You can research it, and I encourage you to do so. It's fascinating.