The impressive defensive system wanted by Sesostri III to establish the border with Nubia, was made with fourteen forts, among which the ones in Buhen, Mirgissa, Shelfak, South Semma, Western Semma and Kumma.
The fort was in the Uronasti Island, in Upper Nubia, it completed the barricade.
These bastions were built with mud bricks and had battled walls plastered with white ivory;
they had covedered passages, slits and could welcome around twothoundred men.
All the forts around the second cataract have been swallowed up by lake Nasser, which was formed after the construction of the Assuan dam.