The Illinois

The Mile High Illinois, Illinois Sky-City, or simply The Illinois was a proposed skyscraper that would have been high, said by Frank Lloyd Wright in his 1956 book, "A Testament". 
The design, was to be built in Chicago, would have included 528 stories, with an area of . Wright said that there would be parking for 15,000 cars and 150 helicopters. 
Chicago is known for good reason as the "Windy City", though it is not the windiest city in the U.S. Had it been built, the Illinois would have been the tallest building in the world by far: more than four times the height of the then tallest building in the world, the Empire State Building, and nearly twice as tall as the world's current tallest building, the Burj Khalifa. 
The building is one of the visionary buildings meant to be an alternative to the increasing urban sprawl occurring in most cities. None of these has ever been viewed as financially feasible.
The design of the Burj Khalifa, the current tallest building in the world, is said to have been inspired by that of The Illinois.