Tonga, officially the Kingdom of Tonga (Tongan: Puleʻanga Fakatuʻi ʻo Tonga), is a state and an archipelago in the South Pacific Ocean. It comprises 176 islands scattered over 700,000 square kilometres (270,000 sq mi) of ocean in the South Pacific. The Kingdom stretches over a distance of about 800 kilometres (500 mi) in a north-south line located at about a third of the distance from New Zealand to Hawaii.

The islands are grouped into four regions.

1. Tongatapu Group – also known as Tongatabu Group, is southernmost island cluster of Tonga.
2. Ha’apai Group – cluster of low coral islands, some volcanic boasting of long stretches of deserted beaches.
3. Vava’u Group – immense land locked harbor, best explored by boat.
4. Niuas – most remote island in Tonga, uplifted volcanic atolls in the far North

Tonga also became known as the Friendly Islands because of the friendly reception accorded to Captain James Cook on his first visit in 1773. He happened to arrive at the time of the ʻinasi festival, the yearly donation of the first fruits to the Tuʻi Tonga, the islands’ paramount chief, and received an invitation to the festivities. According to the writer William Mariner, in reality the chiefs had wanted to kill Cook during the gathering, but could not agree on a plan.