=Wadi Betan= originates on the north side of Gebel Abu Dahr, where an easy pass, 610 metres above sea-level, connects its head with Wadi Um Karaba, and courses at first westward to near Gebel Hendusi; it then turns southward to join Wadi Naam a few kilometres only above its junction with Wadi Hodein. Its total length is over fifty kilometres, and its average slope is about seven metres per kilometre. Only the head of Wadi Betan has been surveyed in detail; but this is the most important part, as containing water sources and old mine workings; and the lower part of its course as shown on the map is probably substantially correct, being based on statements made near the spot by guides familiar with the district. About five kilometres below its head, Wadi Betan contains the two wells called =Bir Betan=. These are excavations in the alluvium of the wadi. The lower one is at the mouth of the small Wadi Um Eleiga, while the other is about 600 metres further up Wadi Betan, close to a small tree. Both these wells were filled up by downwash when I visited them in February 1907, and their places were only recognisable by the clay “hôds” near them; at this time there was no necessity for the Arabs to open them, as a galt at the head of the wadi, just south of the pass into Wadi Um Karaba, was yielding a good supply of water. Just above the wells, Betan receives from the south the feeder called =Wadi Mistura=, draining the west side of Gebel Abu Dahr. The little =Wadi Um Eleiga=, which drains into Betan close to the south well, is of importance as leading to some extensive ruins and old workings about two kilometres up from its mouth. The ruins are mostly rubble hovels, while the workings, which were evidently for gold, vary from mere scratchings to pits ten metres deep in the rock. A diorite mill-stone is to be seen near the ruins.