Soldiers attempting to destroy walls or batter gates were especially vulnerable. As early as the 20th century BC, attempts were made to protect them by shielding them with portable shelters. A scene in the tomb of the 11th Dynasty noble, Khety shows a pair of Middle Kingdom soldiers apparently under the protection of a mobile roofed structure, advancing towards a fortress with a long pole which was perhaps an early battering ram. Egyptian siege warfare was never very effective compared to that of Mesopotamia where battering rams on wheeled carriages, which protected sappers quite well, were developed.
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