A ziggurat is a multi-storied tower with a square or rectangular base. Some ziggurat ruins can still be seen in the Near East, especially in Ur. They were built from piled mud bricks. Ascent was by stairs or ramps. Archaeologists are still unsure exactly what the ziggurats were used for. We do know, however, that ceremonies took place in temples at the top of these structures. These buildings had a strong symbolic dimension and embodied the link between heaven and earth.