Sydney Harbour defences
Coordinates: 33°50′18″S 151°15′21″E / 33.838450°S 151.255930°E Sydney Harbour was protected by coastal batteries and other fixed defences from the early 19th century until the 1960s. These defences were constructed to protect the Australian city of Sydney from attack by enemy warships and submarines.
Sydney's earliest fortifications were built around Sydney Cove to protect the new colony of Sydney from attacks from non-British ships or convict uprisings. The first gun emplacement was built in 1801 on Middle Head (north of Obelisk Bay) during the Napoleonic wars. More permanent fortifications were built during the first half of the 19th century in response to feared foreign attacks and new threats to the British empire. In 1790 the Dawes Point Battery was meant to be the first line of defence against an attack by the Spanish Empire, Napoleon’s French troops in 1810, and the Russian Pacific Fleet in the 1850s (during the Crimean War). This was part of a line of defences that were concentrated on protecting the inner Harbour, these also appear to have been given a low priority. Construction of Fort Denison began in 1841, though the fort was not completed until 1857.
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