The Adelaide River is a river in the Northern Territory of Australia. The river rises in the Litchfield National Park and flows generally northwards to Clarence Strait, joined by eight tributaries including the west branch of the Adelaide River, Coomalie Creek, Margaret River and Marrakai Creek, before discharging into its mouth in Adam Bay in the Clarence Strait. …The Adelaide River is a river in the Northern Territory of Australia. The river rises in the Litchfield National Park and flows generally northwards to Clarence Strait, joined by eight tributaries including the west branch of the Adelaide River, Coomalie Creek, Margaret River and Marrakai Creek, before discharging into its mouth in Adam Bay in the Clarence Strait. The river descends 151 metres over its 238-kilometre course. The catchment area of the river is 7,640 square kilometres.