A huge pyramid had been discovered off the Azores islands by Portuguese amateur sailor Diocletian Silva.
The 60m-tall structure was found underwater between the islands of Sao Miguel and Tercira. Its base measures 8,000 sq m - bigger than a football field - and Silva believes it was man-made.
He says his find may be a remnant of the legendary lost world of Atlantis, which sank into the ocean after a failed attempt to invade Athens.
Silva found the pyramid around five months ago while fishing on his yacht in the area. He discovered the structure through bathymetric navigation and its tip is submerged around 40ft.