Dominating the atmosphere of the town of Siwa are the magnificent jagged ruins of Shali Fortress.  According to ancient Siwan scriptures, 40 Siwans built the fortress in 1203 A.D. to protect the community against raiding Bedouin tribes.  They used kershef, a mixture of mud, sand and sun-dried salt harvested from the Siwa’s salt lakes and combined with palm trunks as ceilings.  In the early 19^th century, encouraged by the security that Egyptian viceroy Mohamed Ali Pasha bestowed on the region, residents of old Shali began moving outside these city walls.  Then, in 1926 unusually heavy rains destroyed much of the ancient citadel, forcing out its remaining residents.  Today, the fortress stands as a testimony to Siwan ingenuity and offers visitors a spectacular view from the upper levels of the old city.