Nightingale Island is an active volcano and one of three islands in the extremes of the South Atlantic Ocean known as the Nightingale Islands falling within the Tristan da Cunha group. The three islands are administered by the United Kingdom and are visited for scientific research purposes and little else. This means the magnificent wildlife with an estimated one million seabirds, in addition to unusual flora, is all unspoiled by people. Nightingale Island is also a protected wildlife reserve and World Heritage Site. Nightingale has two peaks on its north end and the rest of the island is ringed by cliffs and sea caves, and is fringed with kelp beds. The sea caves have been said to hide pirate treasure with a fortune in Spanish doubloons and pieces-of-eight hidden here for safekeeping. However, no recovery of this booty has ever been documented.