Hobart coastal defences

The Hobart coastal defences are a network of now defunct coastal batteries, some of which are inter-linked with tunnels, that were designed and built by British colonial authorities in the nineteenth century to protect the city of Hobart, Tasmania, from attack by enemy warships. During the nineteenth century, the port of Hobart Town was a vital re-supply stop for international shipping and trade, and therefore a major freight hub for the British Empire. As such, it was considered vital that the colony be protected. In all, between 1804 and 1942 there were 12 permanent defensive positions constructed in the Hobart region.

Prior to Australian Federation, the island of Tasmania was a colony of the British Empire, and as such was often at war with Britain's enemies and European rivals, such as France and later Russia. The British had already established the colony of Sydney at Port Jackson in New South Wales in 1788, but soon began to consider the island of Tasmania as the potential site of a useful second colony. It was an island, cut off from the mainland of Australia and isolated geographically, making it ideal for a penal colony, and was rich in timber, a resource useful to the Royal Navy. In 1803, the British authorities decided to colonise Tasmania, and to establish a permanent settlement on the island that was at the time known as Van Diemen's Land, primarily to prevent the French from doing so. During this period tensions between Great Britain and France remained high. The two nations had been fighting the French Revolutionary Wars with each other through much of the 1790s, and would soon be engaging each other again in the Napoleonic Wars.

...
Wikipedia