Excavations carried out in 2004 in the site of Mezad Zohar (Qasr Zuweira), located two kilometers west of the southern Dead Sea, 270 meters below sea level suggest that it was constructed by the Ayyubids and continued to be occupied in the Mamluk period (13th and 14th centuries CE) . The fort was constructed to guard an important pass along the artery between Hebron and fortresses in southern Transjordan. The upper level appears to have functioned as a signal tower that could be seen from the Kerak heights overlooking the Dead Sea on the opposite side of the lake. Muslim sources attest to the importance of the road as part of the 'barid' network in the Mamluk period and refer to the site of az-Zuweir.