What is the narrowest tower in the world?

 The Steinway Tower.

It's the thinnest skyscraper in the world – and as if that weren't remarkable enough, its interior is also extremely luxurious. At 435 meters tall and with a base width of just 17.91 meters, it holds the record for the world's narrowest skyscraper with a ratio of 1:24. The building stands directly on Central Park in New York, on the site of the former headquarters of the renowned piano manufacturer Steinway & Sons.

Ninety-one stories rise into the sky at 111 West 57th Street, defining the New York City skyline. The building contains a total of 46 residential units – some spanning a single floor, others duplexes. The foyers are finished with limestone, marble, blackened steel, and velvet. The floors are made of solid oak in a smoky gray tone. Original works by Picasso and Matisse are also part of the decor.

Why did only WTC's North Tower have an antenna?

 

The towers were built without the antenna. They were so big they broke the city’s television signals, which came from the Empire State Building. A man’s picture had ghosts in it. A problem needed a solution.

The Port Authority owned the buildings, they saw a chance to fix the problem and make money--They decided to move all the city's broadcasters to their new towers. For a clean signal, you only need one mast, one strong source is better than two that could fight each other in the air. So they chose one tower, the North Tower was finished first, so it got the job--It was a practical decision, the 360-foot needle went up. That left the South Tower free for something else--They put an observation deck there instead, a place to sell a ticket to the sky, one tower for the broadcasters, one for the tourists.