4. 601 Lexington Avenue: A seven-story atrium

Photo by Atilla Sary

601 Lexington Avenue building (formerly known as the Citigroup Tower) sits on massive columns that make it look as if it is floating on air. What is exciting is the seven=story atrium at the base of the building. This space, renovated in 2009, contains ample indoor and outdoor space including a sunken plaza that leads to one of the busiest subway stations in New York City. Here you can grab some coffee or a snack at one of the kiosks or many restaurants, sit and enjoy yet another waterfall, and shop in one of the shops.