Ziggurats were important in ancient Mesopotamia. The tradition of building a ziggurat was started by the Sumerians. Ziggurats went up to be nearly 300 feet tall and 300 feet by 300 feet square at its base. Ziggurats showed that the city was dedicated to a god. At the very top of the ziggurat was a shrine to the god. There, the priests would perform religious events. The reason they built them high was because they wanted the shrine to be close to the heavens. To them, it was a bridge between heaven and earth. Later on, ziggurats became not only the center of religion, but also the center of learning for the entire community.