Easter Island:

This Island is a Polynesian island in the southeastern Pacific Ocean, at the southeastern most point of the Polynesian triangle. The history of this island is rich and controversial. Its inhabitants have endured famines, epidemics, civil war, and slave raids and near deforestation; its population declined sharply more than once.

However these statues still remains a mystery for the researchers. The statues in the island are over fifty feet tall. But no one has a clue who built them? Why they were built? How they were brought there and so on. One of the theories is that a civilization had lived here long ago, but the people ate everything on the island and either they have moved some where else or they were exterminated.