Fort Denison, which can be seen from Mrs Macquaries Seat, was used in the early days of settlement as a place of punishment and confinement for the convict population. During the mid 19th century a fort was built on the island to protect Sydney Harbour.

Fort Denison is now a tourist destination and is open seven days a week for lunch at the cafe or for picnics with a tour group. There are two tours daily to Fort Denison and tours can be booked by visiting the Sydney Harbour National Park Information Centre, located in The Rocks or by ringing +61 2 9247 5033

Getting there, further details and event booking information.

Other islands on Sydney Harbour include:
Clark Island
Cockatoo Island
Goat Island
Rodd Island
Shark Island