Lake Disappointment — now officially known by its traditional Martu name, Kumpupintil Lake — is one of Australia's most remote and geologically fascinating water bodies, situated in the Little Sandy Desert approximately 300 kilometres east of Newman in Western Australia. Resting at an elevation of 325 metres above sea level, this vast endorheic salt lake stretches roughly 160 kilometres in length and covers a surface area of around 330 square kilometres. As an endorheic basin, the lake retains any water it receives with no outflow, meaning it fills only during exceptionally wet periods and is dry the vast majority of the time. The lake sits on the edge of the Gibson Desert, with Karlamilyi National Park — Western Australia's largest and most remote national park, spanning over 1.3 million hectares — located to the north. The surrounding landscape is characterised by arid desert terrain, claypans, and sparse desert vegetation, making this one of the most isolated locations in the country.