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The silty sediments which occur in eleven outcrops of four wadis in the Central Sinai, Egypt, are true loesses in origin, having been transported from the Gulf of Suez which was dry during Pleistocene times. After sedimentation of the eolian material on the slopes of the wadis and in the wadis, the silts have been washed out by the rain into the wadi system. The meandering mixed load rivers transported the fine silts in suspension, whereas the accompanying sands and gravels of fluvial/torrential origin have been transported along the base of the river beds. In times of high water the silts flooded the riverbanks and deposited on areas beyond the "levees" (overbank fines, crevasse splays). The coarser material accumulated as point bar deposits in river bends and in front of obstacles on the base of the river. This model is applicable for most of the silt occurrences in the wadis of central Sinai. Only at El Bueib (the Oasis of Feiran) the fabric and geomorphology demand a lacustrine milieu for sedimentation. On the basis of mineralogical and geochemical analysis, changes in paleoclimatology are proposed for a period of 6,000 years.