Lake Eyre, about 700 kilometres north of Adelaide, is the heart of the extensive Lake Eyre Basin stretching north to Longreach, Blackall and Winton in Queensland and Alice Spring in the Northern Territory. Lake Eyre is in desert and rainfall is usually insignificant in determining the level of water in the lake which relies on inflow from the Diamentina and Georgina Rivers and Coopers Creek draining the Channel Country (in theory the Finke River in the Northern Territory also contributes to Lake Eyre but the Simpson Desert absorbs most, probably all, water in the Finke). The Queensland rivers rely on monsoonal rainfall for their water and are usually dry so Lake Eyre is normally mostly salt flats. When seasonal rain falls in the headwaters varying amounts reach Lake Eyre because of the quantity soaked into desert, absorbed by extensive wetlands, or evaporated along these rivers. Lake Eyre is rarely full of water.
The Lake Eyre complex comprises the larger Lake Eyre North and smaller Lake Eyre South joined by the 15 kilometre long Goyder Channel on the east. The southern part of Lake Eyre North is divided into three bays (Belt Bay, Jackboot Bay and Madigan Gulf). The deepest part is in Belt Bay where bottom levels of 15.2 metres below sea level have been recorded making this the lowest point on the Australian continent. The floor of Lake Eyre North is generally flat so precisely defining the deepest part is difficult. Water entering Lake Eyre North at the Warburton River (from the Diamentina and Georgina Rivers) flows down the Warburton Groove (up to 5 km wide and 0.6 metres deep) to reach Belt Bay.