John Hoopes, who researches ancient cultures of Central and South America, is one of the world's foremost experts on the Costa Rican stone spheres, made famous by Indiana Jones' "Raiders of the Lost Ark". Although the stone spheres are very old, international interest in them is still growing.
According to Hoopes, around 300 balls are known to exist, with the largest weighing 16 tons and measuring eight feet in diameter. The KU researcher said that scientists believe the stones were first created around 600 A.D.
Speculation and pseudoscience have plagued general understanding of the stone spheres. For instance, publications have claimed that the balls are associated with the "lost" continent of Atlantis. Hoopes has a created a popular Web page to knock down some of the misconceptions about the spheres. He said the stones' creation, while vague, certainly had nothing to do with lost cities or space ships.
I say "Who really knows....?"