The shuttle imaging radar experiment (SIR-A) in 1981 revealed a complex of previously unknown, channel-like features beneath the sandsheets of the Eastern Sahara. Since the age and significance of these features could not be otherwise determined, a survey of the archaeology of the region was undertaken to provide at least a minimal age for them and to evaluate their potential as reservoirs of Pleistocene and Holocene rainfall. The results indicate that the features predate all detectable human activity in the area and are likely to be earlier than Pleistocene, and that there is no evidence that they now hold, or have held since at least the Middle Pleistocene, significant quantities of water. The area of the channels may have been no more than marginal to human economic systems, even during the wetter phases of Saharan prehistory.