Bare Island Fort reflects the development of coastal fortifications design by the British Army, from locations around the world over more than a century. This was combined with a newly generated understanding of ballistics and materials science that was a product of the late nineteenth century Industrial Revolution. Bare Island, in comparison to earlier coastal defences constructed in Australia, such as Fort Denison or the Middle Head Batteries, shows the impact of new materials such as concrete, as well as the ever-increasing power of guns.