A strange structure is found in Mongolia. Is it the lost tomb of Genghis Khan? Bizarre rings in Spain could lead to the lost city of Atlantis. A huge floating island is on a collision course with New Zealand. Just what on earth are they?

Satellites find a great scar in the desert, it might be the key to finding the last wonder of the ancient world; Clues to the location of infamous City of Gold, El Dorado.