Seal Island is a small land mass located 5.7 km off the northern beaches of False Bay, near Cape Town, in South Africa. The island is so named because of the great number of Cape Fur Seals that occupy it. It is 5 acres (2.0 ha) in area and home to 64,000 cape fur seals. It is home to sea birds too and it is likely that non-marine species (in no great number) fly there to breed as well (see external link to the Avian Demographic Unit at the University of Cape Town). The island is an outcrop of the Cape granite and rises no more than about four to six metres above the high tide mark. The island is long and narrow- 800 metres by 50 metres. There is no vegetation or soil of any significance and no beach. A radar mast was built on the island during World War II by a crew who lived in prefabricated huts for the duration of the construction but this tower gradually succumbed to corrosion and was blown over in a winter storm in 1970. All that remains of it is rusty, twisted metal. There are the ruins of a few huts and other structures from the sealing and guano-collection era (first half of the 20th century).