The construction of the United Nations Headquarters in the early 1950s, on a site previously occupied by slaughter houses, dramatically transformed Turtle Bay east of Second Avenue into a center of international diplomacy. This tour will explain the development of the UN complex itself and examine the most notable modern and contemporary architecture in the surrounding area. Among the nearby permanent missions to the UN, prominent non-profit institutions and luxury high-rise apartment towers are works of three Pritzker Prize winners: Kevin Roche, I.M. Pei and Norman Foster, along with projects designed by SOM, Harrison & Abramovitz, Gwathmey Siegel & Associates, William Lescaze, and Charles Correa. Note: this tour will not go inside the UN Headquarters. Tour guide John Arbuckle is President of DOCOMOMO US/New York Tri-State, the local chapter of an international organization dedicated to preserving Modern architecture.