D'Entrecasteaux Channel in the context of Derwent River (Tasmania)

Bruny Island is a 362-square-kilometre (140 sq mi) coastal island of Tasmania, Australia, located at the mouths of the Derwent River and Huon River estuaries on Storm Bay on the Tasman Sea, south of Hobart. The island is separated from the mainland by the D'Entrecasteaux Channel. The island and the channel are named after French explorer, Antoine Bruni d'Entrecasteaux.

The island's Aboriginal name is lunawanna-allonah, from which the island settlements of Alonnah and Lunawanna are named.

The Huon River (/ˈhjuːɒnˈrɪvə/ HYOO-on-RIV-ə, Mellukerdee/palawa kani: Taloonne) is a perennial river in the southwest and southeast regions of Tasmania, Australia. At 174 kilometres (108 mi) long, the Huon River is the fifth-longest in the state, with its course flowing east through the fertile Huon Valley and emptying into the D'Entrecasteaux Channel, before flowing into the Tasman Sea.

At its mouth, the Huon River is over 5 kilometres (3 mi) wide, and in the lower reaches, the river's average depth is 3 metres (10 ft), with maximum depths of up to 12 metres (39 ft). The Egg Islands, in this lower tidal zone, are ecologically significant for their rich wetlands and birdlife.

Alonnah is a rural locality on Bruny Island in the local government area (LGA) of Kingborough in the Hobart LGA region of Tasmania. The locality is about 60 kilometres (37 mi) south (by ferry) of the town of Kingston. The 2021 census recorded a population of 164 for Alonnah.

It is a small township on the western side of Bruny Island, facing the D'Entrecasteaux Channel.

Lunawanna is a small township on the western side of Bruny Island, Tasmania, facing the D'Entrecasteaux Channel. It is named after part of the Tasmanian Aboriginal name for Bruny Island, Lunawanna-alonnah, a nearby township about 5 kilometres (3.1 mi) to its north being named Alonnah.

Lunawanna is in the federal electorate of Franklin, the Tasmanian House of Assembly division of Franklin, and the Tasmanian Legislative Council division of Huon. The Bruny Island local council amalgamated with Kingborough council in 1994 and Lunawanna is located in the Kingborough Council local government area.