A MYSTERIOUS skyscraper that towers over New York City's iconic skyline has led to crazy rumours of what the huge building's really used for.
The creepy 40-storey building has been called a vampire lair, and the headquarters for the Men in Black - and has even scared legendary actor Tom Hanks.
The menacing skyscraper is made of concrete and has no windows - making it stand out in bustling New York.
When Hanks saw it in 2017, he took to X, formerly known as Twitter, to say: “This is the scariest building I've ever seen!
“WTF goes on inside??”
Crazy conspiracies have spread online about the building with one person writing: “Gives off MI-6 vibes,” and another joking: “Lizard people don't need windows.”
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But the truth behind the eerie skyscraper is much simpler.
Once known as the Long Lines Building, the tower was built between 1969 and 1974 for the American Telephone and Telegraph Company- one of the most important telecommunications hubs in the US.
The equipment needed a unique space and a secure location, so the building's floors are higher than normal.
This means the 40-story tower, actually only has 29 floors.
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It’s also rumoured to be able to withstand a nuclear blast and holds enough food to keep 1,500 people alive for two weeks.
It was used until 1999, when the company moved away.
Today, the skyscraper is still used by some local exchange carriers to store telephone switching equipment but it’s reportedly also a high security data centre.
Renamed 33 Thomas Street, after its address, the building remains suspicious to some.
A 2016 investigation by revealed that there's more than meets the eye to the building.
Alongside a multitude of conspiracy theorists, they tried to prove that it's a secret National Security Agency (NSA) base.
Their investigation, that includes leaked documents by whistleblower Edward Snowden, provides “compelling evidence” that the skyscraper is codenamed TITANPOINTE by the NSA.
Allegations of a major international “gateway switch" that routes phone calls between the US and countries across the world was also apparently inside the windowless structure.
If true it could be the most important NSA surveillance site in the US.
The leaked Snowden documents claimed the tower was used for spying on phone calls, fax messages and internet data under the name Project X.
The NSA declined to comment on any of the revelations and left what's inside a mystery.
Social media has been left divided on what goes on behind the concrete walls.
One Redditor said: “It’s a telecom central office no big mystery at all, most major cities have several.”
Meanwhile X users had more wild theories: “So is this where all the vampires live now,” said one, while another put: “Looks like something that should be in Dune.”
The vampire theory has proved the most popular so far, with the lack of windows preventing sunlight coming through.
Lizard people, little green aliens, Men in Black and Batman have all also been thrown out online as people try to solve the mystery.
Creepy buildings are all over the world such as a 49-storey skyscraper in Bangkok.
The abandoned building, dubbed the “ghost tower” was never finished and is now just a lookout for birds and bats in Thailand.
Meanwhile, a hotel in the Spanish holiday resort of Tenerife has sat empty for half a century.
And a 25-storey tower block in Mexico City has been abandoned for the past 40 years, surviving six earthquakes during that time.
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Elsewhere in Tenerife, an abandoned hotel has mysteriously sat empty for 50 years.
The 22-storey Añaza hotel sits on the shores of Los Pocitos village but has not had a single guest.