The Gilbert River is located in Far North Queensland, Australia. When combined with the Einasleigh River, the river system is the largest river system in northern Australia.
The Gilbert River rises below Conical Hill in the Einasleigh Uplands, draining the eastern slopes of the Gregory Range and the western slopes of the Newcastle Range, north of Hughenden. The river flows generally northwest, joined by forty tributaries that drain the Blackbraes National Park including, from source to mouth, the Styx, Percy, Robertson, Langdon, Little, and Einasleigh rivers and numerous creeks. North of Karumba the Gilbert discharges into the Gulf of Carpentaria. However, northwest of Normanton an anabranch of the river forms confluence with the Smithburne River, also emptying into the Gulf. The Gilbert River has a catchment area of 22,041 square kilometres of which 455 square kilometres, or a third of the total catchment, is a vast estuarine delta approximately 100 kilometres wide that largely consists of tidal flats and mangrove swamps across the Gulf Country. The river descends 635 metres over its 887-kilometre course.
The Gilbert River is a seasonal stream and discharge can vary greatly depending on the intensity of the monsoon. When combined with the Einasleigh River, the Gilbert River has the sixth-highest discharge of any river in Australia.
