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Kharga Oasis, in Egypt's hyperarid Western Desert, today lacks naturally occurring surface water. Near Kharga, large tufa deposits ranging from a few hectares to more than 10 km(2) in area dot the edge of the Libyan Plateau. These, and lacustrine sediment, record intervals during the Pleistocene when wetlands, ponds, and small freshwater lakes provided water to enable herbivore and human inhabitation. Along with Pleistocene fossils, archaeological finds in the area include artifacts from Earlier Stone Age, Middle Stone Age, Later Stone Age, and younger cultural materials. ESR analysis was used to date freshwater mollusc shells (Melanoides tuberculata and Gyraulus) found in tufas and lake silts at Wadi Midauwara, Matana, and Bulaq. In some units, multiple gastropod populations from different times have been preserved as a mixed deposit, while several others appear to only preserve a single population. The mollusc dates suggest that freshwater existed sporadically at Bulaq and Matana during Marine (Oxygen) Isotope Stages (MIS) 2 and 4. At Midauwara, standing freshwater existed during the MIS 7/6 and 6/5e boundaries, and repeatedly in MIS 5-2. Molluscs and water also existed during the earliest Pleistocene, at similar to 2.4 +/- 0.4 Ma, which could have enabled the first hominin migration out of Africa via the Western Desert.