Fortress on the west bank of the Nile, close to the Second Cataract. Here, where the Nile Valley is at its narrowest and thus easy to control, the kings of the 12th Dynasty built a number of fortresses to control border traffic. Senwosret III erected a pair of stelae here, one giving a vivid account of the king's actions against Nubians trying to move northwards, and the other recording his order that no Nubian (not even his cattle) may pass the border, except to trade. Some papyri contain notes about what went on at the border and they confirm that this order concerning trade was obeyed to the letter. Excavations in the area, before it disappeared under the waters of Lake Nasser, revealed living quarters, temples and cemeteries as well as the fortress itself.