The headquarters of the United Nations is a complex in New York City designed by Brazilian architect Oscar Niemeyer. The complex has served as the official headquarters of the United Nations since its completion in 1952. It is located in the Turtle Bay neighborhood of Manhattan, on spacious grounds overlooking the East River. Its borders are First Avenue on the west, East 42nd Street to the south, East 48th Street on the north and the East River to the east. The term “Turtle Bay” is occasionally used as a metonym for the UN headquarters or for the United Nations as a whole.