St. Matthew Island (phantom island) and H.C. Adams (1883) suggest that the error may have arisen from a confusion with Annobón Island, which lies at the same latitude but at 5°38′E longitude. St. Matthew Island (phantom island) St Matthew Island is a phantom island once thought to lie roughly one thousand kilometers northeast of Ascension Island in the Atlantic Ocean. It appeared on navigational charts until as late as the early twentieth century. It was supposedly located at approximately 2°S 8°W, and was alleged to have been discovered by the Portuguese on St. Matthew's Day 1516. It was shown and named on several maps going
Rottnest Island the 17th century, by which time it was uninhabited. The island was named by Willem de Vlamingh in 1696, who called it "'t Eylandt 't Rottenest" ("Rats' Nest Island") after the quokka population. Since the establishment of the Swan River Colony by British settlers in 1829, the island has variously hosted a penal colony, military installations, and internment camps for enemy aliens. Many of the island's buildings date from the colonial period, often made from locally quarried limestone, and are now used as accommodation for holidays. Rottnest Island was inhabited by Aboriginal people until rising sea levels separated the island