Hao, or Haorangi, is a large coral atoll in the central part of the Tuamotu Archipelago. It has c. 1000 people living on 35 km2 (14 sq mi). It was used to house the military support base for the nuclear tests on Mururoa. Because of its shape, French explorer Louis Antoine de Bougainville named it "Île de la Harpe".

The Tuamotu Archipelago or the Tuamotu Islands are a French Polynesian chain of just under 80 islands and atolls in the southern Pacific Ocean. They constitute the largest chain of atolls in the world, extending over an area roughly the size of Western Europe. Their combined land area is 850 square kilometres. This archipelago's major islands are Anaa, Fakarava, Hao and Makemo.