Siege weapons can destroy buildings, but are weak against other units, especially cavalry. One of the machines developed to attack walled towns was the siege tower on wheels. This large wooden tower was covered with wet hides to minimize its vulnerability to fire. A battering ram was suspended inside for use against the wall the tower was moved against. The tower protected the men working the ram and other men shooting arrows into the town. When the wall was knocked down by the ram, the attacking army could enter the city.
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