432 Park Avenue, New York

Measured to its roof (1,396 feet above the street), the slender residential tower at 432 Park Avenue is the tallest building in New York City, and the second tallest building in the country (after the Willis/Sears Tower in Chicago). Despite its height, 432 Park Avenue has a base of only 100x100 feet, making it likely the most expensive 10,000 square feet of ground in the nation.