 Construction of the fort began in 1878 . It was officially opened in October 1880 and completed by 1882 . Due to changes in the Port River and shipping movements , Fort Largs surpassed it for strategic importance by 1890 . By the close of the 19th century , the fort was largely unused and had no defence significance . It was briefly used for military purposes during World War I and World War II , though not for its original defensive role . For much of the 20th century the area was put to a variety of uses including accommodation , a caravan park and a boy scout <unk> . After coming into state government hands in 1951 it was declared as a conservation park and is now managed by the Department of Environment , Water and Natural Resources ( DEWNR ) ; preserving and showcasing its historic value . The fort and surrounds occupy the northern half of the 5 @-@ hectare ( 12 @-@ acre ) conservation park , the southern half is a caravan park . The fort is a lunette shaped defensible battery that was supported by land forces for self @-@ defence . When constructed it was seen as state of the art , incorporating powerful and modern weapons . Its main armament is two rifled muzzle @-@ loading ( RML ) 10 inch 20 ton guns backed up by two RML 64 pounder 64 cwt guns , both rare in their particular configuration . The fort retains its original 19th century cannons and three have been restored to working condition . 
