In 1855, during the Crimean War, Governor William Denison reclaimed the tip of Kirribilli Point, on which fortifications were built. These fortifications, along with Fort Denison, were intended to strengthen the defences of Sydney Harbour, as it was feared that the Russians might attack. In 1856, Lieutenant-Colonel George Barney, a Royal Engineers officer, lived in "Wotonga" and designed and supervised the installation of a battery of five, muzzle-loading guns on Kirribilli Point, as well as constructing the martello tower at Fort Denison.