A Moreton Bay island with beautiful beaches, significant cultural heritage values and natural conservation values, both terrestrial and marine. Important historic features include remnants of a quarantine station and a multiracial lazaret.

The 519 ha island is surrounded by mangroves, except for a sand beach on the southern side that forms Horseshoe Bay. Rich in cultural significance, Teerk Roo Ra is the only intact example of a multiracial lazaret in Australia. It opened in 1907, housing leprosy patients for the next 52 years. Prior to the lazaret, the island served as a quarantine station (1874 to the 1890s) and home for 'inebriates' (1910–1916).