33 Thomas Street, Brutalist skyscraper in Tribeca, Manhattan, United States.

33 Thomas Street is a 170-metre (550 ft) windowless skyscraper on the east side of Church Street between Thomas and Worth Streets in Tribeca, Lower Manhattan. Its facade is entirely covered with precast concrete panels clad in flame-treated textured Swedish granite, pale grey and set in a grid, with six large protrusions housing air ducts, stairs and elevators. Recessed openings near the roofline hold ventilation equipment on the 10th and 29th floors.

AT&T began construction in 1969 to create a telecommunications center that was completed five years later, replacing older cast-iron structures in Lower Manhattan. Architect John Carl Warnecke designed the tower to withstand extreme conditions and serve long-term critical network operations.

The building's nickname comes from the AT&T Long Lines Department, which occupied it and became AT&T Communications in 1984 after the Bell System breakup. The facade is precast concrete clad in flame-treated textured Swedish granite, and the 10th and 29th floors carry protruding ventilation openings. William H. Whyte called it the tallest blank wall in the world.

The tower stands at the corner of Thomas Street and Church Street in Tribeca, a few walking minutes from City Hall and the World Trade Center. The interior is not open to the public, but the exterior can be viewed easily from surrounding streets, especially during clear daytime weather.

The building was designed to be self-sufficient with its own gas and water supplies and protected from nuclear fallout for up to two weeks after a nuclear blast. In 2016, journalists Ryan Gallagher and Henrik Moltke reported in The Intercept that it is an NSA mass surveillance hub code-named TITANPOINTE, drawing on Edward Snowden's disclosures.