Snohetta completes "surgical" renovation of Phillip Johnson's AT&T building

Architecture studio Snøhetta has carried out a series of renovations to the postmodern 550 Madison skyscraper, which was formerly known as the AT&T building.
Snøhetta opened up some of the facades, added a public garden and improved ventilation and elevation systems as part of the conversion of the 647-foot-high (197-metre) skyscraper from a single-occupant tower into an office for multiple occupants.
Top: The crest of 550 Madison. Photo by Alex Fradkin