Ziggurats are, architecturally, the Mesopotamian equivalent of the Egyptian pyramids: large artificial square mountains of stone. They were built using different materials. The pyramids were built from stone and the ziggurats from mud brick. This would have caused the Mesopotamian bricks to fall apart and break more easily, as for the Egyptian bricks were stable, stronger and durable. Hope I helped. :)
Egyptian pyramids have survived due to their use of durable stone materials, a favorable dry climate, and their cultural significance as tombs. In contrast, Mesopotamian ziggurats were made of less durable mud bricks, subject to erosion and weathering, and required frequent rebuilding. These factors contributed to the difference in preservation between the two architectural forms.
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