Slender Towers
Developments in building technology and advent of new materials in recent years are making it possible to build slender towers that are among the tallest in the world. These cloud-puncturing beanstalks are poised to transform city's iconic skyline. So far the thinnest of all is the recently completed tower at 432 Park Avenue in New York City.

The stark white pillar, is 1,396 feet tall, but each side is only about 93 feet wide, higher than the Empire State Building as wide as the length of a basketball court. Plans are in place for another tower just a few blocks away that could be the skinniest skyscraper in the world at 1,400 feet and under 60 feet wide.