The ziggurat was the centrepiece of a new city built by the Elamite king Untash-Napirisha (ruled c.1260 - 1235 BC). After his death, however, the Elamite capital returned to Susa - although Choga Zanbil was still an Elamite city until the Assyrians destroyed it in around 640 BC. Ziggurats were being built all over Mesopotamia from about 5000 BC: all consist of a series of rectangular platforms on top of each other - with a temple at the top. The shape was perhaps inspired by Egyptian pyramids - but ziggurats were solid, with no tombs concealed in them. The biblical story of the tower of Babel arose from the great temple of Marduk in Babylon.
The ziggurat at Choga Zanbil is approximately 100 metres square. It was surrurounded by an inner and an outer wall, between which were a number of temples to lesser Elamite dieties - assuming the main temple was for Inshushinak. One of the workmen 3,250 years ago left his footprint in the damp clay.