Hudson Yards is the largest private real estate development effort in the U.S. The 28-acre mixed-use site along Manhattan's West Side offers over 27,000,000 square feet of office and retail space. 66 Hudson (pictured left) is also known as "The Spiral." It is a 65-story, 1,031-foot-tall office skyscraper with 2,850,000 square feet of space. 20 and 30 Hudson Yards are pictured below.