Say hello to the 33 Thomas Street Building. Located in Manhattan, NY in Tribeca, it stands 29 stories (550ft) tall and is commonly known as the Long Lines Building. Built in 1974, its easily the strangest and most curious skyscraper in New York's world famous skyline.

The building is officially owned and operated by AT&T, serving as a telephone/long distance exchange and secure data center space, and is reportedly one of the most important telecommunication hubs in the country. Outside of AT&T, it is not known to house any other occupants.

Other than its main entrance, the skyscraper oddly has no external windows, only a series of ventilation openings at the 10th and 29th floors. It is a highly secured building. No one is allowed inside without authorization and authorization is not granted to the public.

This is where it gets interesting. The structure is reportedly designed to survive a nuclear blast and subsequent radioactive fallout. It houses enough food to feed 1,500 for 2 weeks in the event of a catastrophe. But its rumored to be much more than a doomsday shelter...

The building is also believed to house one the most important National Security Agency surveillance facilities on US soil. Documents obtained from infamous whistleblower Edward Snowden point to it as the location of a top secret NSA surveillance site code-named TITANPOINTE.

If the NSA wanted to surveil/intercept domestic or foreign communications utilizing private sector telecommunications infrastructure, this is the place to do it. According to a former AT&T engineer, inside lies a major international "gateway switch" that routes phone calls...

...between the US and countries around the world. It is believed the facility provides the NSA with a location and means to target and collect Intel on organizations like the UN, the IMF and the World Bank, in addition to US allies like Japan, Germany, and France among others.

It's long been known that AT&T has cooperated with the security agency to conduct surveillance and gather meta data, but more recent evidence suggests the NSA uses the facility to conduct taps of the domestic phone calls, messages, faxes and internet data the company facilitates.

While there is yet to be any official recognition of the building as National Security Agency asset, the evidence is quite overwhelming. "Coincidentally" the building directly next door to 33 Thomas Street, 26 Federal Plaza, is home to many federal agencies including the FBI.