The structure, estimated as being between 3.5 and 11 miles across, was spotted on Google Earth in the Pacific Ocean just west of Mexico. A video about the discovery uploaded to YouTube has drawn vast speculation about what it could be, including an ancient sunken city, a bizarre UFO, or even an alien base. The "discovery" was made by Argentinian Marcelo Igazusta.

The 'pyramid' was spotted on Google Earth

He says in a video about the find it is an alien UFO left underwater. The video commentary described it has being "an intense light in the Pacific Ocean" of 3.5 miles in length, with a shape similar to a plane. Scott C Waring, an alien conspiracy theorist, said: "It is a perfect pyramid that measures over 8.5 miles across one side of its base. Thats a conservative estimate, it could be up to 11 miles across.” He suggested it could symbolise an ancient civilisation, or even something alien.

Conspiracy theorists claim it could be an undersea ancient pyramid or even connected to aliens.

A 8.5 mile pyramid...biggest the world has ever known, and it’s right off of Mexico, near the ancient Mayan and Aztec pyramids. Scott C waring

He said: ”Even if this is not a UFO that landed in the ocean that was being used as an alien base, it still is a monumental discovery. "A 8.5 mile pyramid...biggest the world has ever known, and it’s right off of Mexico, near the ancient Mayan and Aztec pyramids." His reasoning that aliens might be involved? He said: "Humans could never have built such a construction. Only aliens could accomplish making such a massive structure." Case closed?

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