Hobart is the capital and most populous city of the Australian island state of Tasmania. With a population of approximately 225,000. Since its foundation as a colonial outpost, the city has expanded from the mouth of Sullivans Cove in a generally north-south direction along both banks of the Derwent River, from 22 km inland from the estuary at Storm Bay to the point where the river reverts to fresh water at Bridgewater. Hobart has a mild temperate oceanic climate. Hobart is an Antarctic gateway city, with geographical proximity to East Antarctica and the Southern Ocean.