Saint John's Island also known as Saint John's is the largest of the Southern Islands in Singapore. It is located approximately 6.5 km to the south of the main island of Singapore, off the Straits of Singapore. It is accessible be taken by a boat from Marina South Pier. Saint John's Island formerly housed a quarantine station for cholera cases detected among immigrants in the late 19th century, and starting from 1901, victims of beriberi were also brought to the island. By 1930, the island gained world recognition as a quarantine centre screening immigrants and pilgrims returning from Mecca. The quarantine station was eventually also used to house victims of other diseases, such as leprosy. When mass immigration was closed in mid-20th century, the island was used to house a penal settlement and from 1955 a drug rehabilitation centre. The 40.5-hectare hilly island was transformed in 1975 into a tranquil getaway with swimming lagoons, beaches, picnic grounds, trekking routes and football fields. The island is also a haven for a host of flora and fauna, and is popular for weekend visits. There is also a small jetty at the southern end of the island to transport visitors to and from the mainland. The island, reputedly haunted according to some localtraditions, was the site of Sir Stamford Raffles's anchorage before meeting the Malay chief of Singapore in 1819. Also located on the island is the Tropical Marine Science Institute, Agri-Food & Veterinary Authority of Singapore's Marine Aquaculture Centre. A detention centre for illegal immigrants still remains. Holiday-makers yearning for an island stay on Saint John's Island can book the Holiday Bungalow, which can accommodate up to 10 persons and comes furnished with a kitchen. Organised groups can stay over in the dormitories at the Holiday Camps which can take up to 60 persons. The dormitories are equipped with basic cooking facilities. Overnight stays are only allowed for occupants at the Holiday Bungalow and Holiday Camps.