This 46-floor tower is one of NYC's most creative works of contemporary architecture, not to mention one of its greenest; around 90% of its structural steel is from recycled sources. Designed by Foster & Partners', its diagonal grid of trusses evokes a jagged glass-and-steel honeycomb. The tower rises above the hollowed-out core of John Urban's 1928 cast-stone Hearst Magazine Building and the lobby is home to Richard Long's Riverlines , a 70ft mural made using mud from New York's Hudson River and England's River Avon.
