The two principal islands of the Regency are
Kei Besar (
Greater Kei) in the east and the slightly smaller (excluding those parts of the island now in Tual City) but more densely populated
Kei Kecil (
Lesser Kei) in the west. The capital is located at Langgur on Kei Kecil. The third-largest island in the group,
Dullah, on which the city of Tual is located, is no longer within the Regency. Kei Besar is long, thin and mountainous. Kei Besar's topography varies between 500 and 800 metres above sea level, and differs from the islands to the west by having a
karst formation in the middle of it. Kei Kecil (also called Nuhuroa) is more low-lying, not exceeding about 100 metres above sea level, and contains much swampland; the regency's nominal capital, Langgur, is situated in the north-east of the island, just across a tiny channel from Tual on Dullah Island, and effectively forms a suburb of the City of Tual. About 50 smaller, forest-covered coral islands lie of the west coast of Kei Kecil; about 33 are part of Kei Kecil District, including Ngaf, Ohoitir, Ohouwa, Nai, Warhu, Hoat and Tangwain; about 16 are part of Kei Kecil Barat District, including Lik, Tarwa, Waha, Warbal, Manir, Ur, Witir, Nuhuta and (further south) Tanimbar Kei. Further groups of islands which lie more to the west (but geographically part of the Kei Islands) form part of Tual City - including the
Tayando-Tam group of 27 islands and (even more to the west) the
Kur group of 9 islands. == Administrative districts ==