The Murrumbidgee River is a major tributary of the Murray River within the Murray–Darling basin and the second longest river in Australia. It flows through the Australian state of New South Wales and the Australian Capital Territory, descending 1,500 metres (4,900 ft) over 1,485 kilometres (923 mi), generally in a west-northwesterly direction from the foot of Peppercorn Hill in the Fiery Range of the Snowy Mountains towards its confluence with the Murray River near Boundary Bend.

The Murray River is a river in Southeastern Australia. It is Australia's longest river at 2,508 km (1,558 mi) extent. Its tributaries include five of the next six longest rivers of Australia. Together with that of the Murray, the catchments of these rivers form the Murray–Darling basin, which covers about one-seventh the area of Australia. It is widely considered Australia's most important irrigated region.