Atafu

Atafu, formerly known as the Duke of York Group is a group of coral islets within Tokelau in the south Pacific Ocean. Covering 2.5 km2, it is the smallest of the three islands that constitute Tokelau, and is composed of an atoll surrounding a central lagoon, which itself covers some 15 km2. The atoll lies some 800 kilometres south of the equator at 172° 30' West, 8° 35' South.

The main settlement on the atoll is located on Atafu Island at the northwestern corner of the atoll. The atoll is roughly triangular in shape and encloses a lagoon some five kilometres north to south by four kilometres east to west at its widest point. It is low-lying, reaching a maximum altitude of only some five metres, and is heavily vegetated notably with coconut palms.

The eastern side of the lagoon is a nearly continuous thin strip of land with one small break halfway along its length. In contrast, the western side is composed of reef and several distinct islands, notably the inverted V shape of Atafu Island in the north, Alofi, which extends into the lagoon from the western reef, and the L-shaped Fenualoa in the southwest. The smaller Tamaseko Island lies in the lagoon close to Alofi.

The reef which connects the islands of the atoll is shallow enough that it is possible to walk between the islands at low tide. This also means that there is no boat passage to the lagoon, although the ocean becomes deep very close to the reef. This allows for good anchorage, but also makes for rough seas close to the reef. The flatness of the atoll and its location within the tropical cyclone belt has led to damage to island properties on occasions, and Atafu's existence may become endangered if sea levels rise due to global warming.

It is likely that Polynesians at least visited the island in prehistory but may not have settled there on a permanent basis. The European discovery of the atoll came in 1765, by John Byron, of the HMS Dolphin.