What then do we know about city and its structure from the excavations have taken place city seems to been divided into two religious sections – the Ianna district and the Anu district, named after the goddess Inanna and her grandfather Anu, together with surrounding residential areas. There is no doubt that the temples stood at the heart of the city. In the Gilgamesh epic, we are told that the Temple dedicated to Ianna covered one third of the area of the city.
The Ianna complex was contained by a wall which separated it from the rest of the city, although it is unclear whether this was for ceremonial purposes or for some other reason.
It has been suggested that Anu was the patron God of the original early city until the rise of the worship of Ianna, when she was given her own ‘city area within the city – a private compound if you like’. Since some temples were considered the literal dwelling places of deities on Earth and since the evidence seems to suggest that Ianna was believed to be a goddess who preferred things her own way, some have suggested this might be the reason for the walled enclosure, but really this is just speculation. The Anu district was smaller but would have looked impressive from a distance since unlike the temple complex of Ianna its dominating feature was a ziggurat.
Ziggurats were built by many of the Mesopotamian races from 4000 BCE until around 600BCE. Built in receding tiers upon a rectangular, oval, or square platform, the ziggurat was a pyramidal structure with a flat top. Sun-baked bricks made up the core of the ziggurat with facings of fired bricks on the outside. The facings were often glazed in different colors and may have had an astrological significance. The number of tiers ranged from two to seven. It is assumed that they had shrines at the top, but there is no archaeological evidence for this and the only textual evidence is from Herodotus. Access to the shrine would have been by a series of ramps on one side of the ziggurat or by a spiral ramp from base to summit. The Mesopotamian ziggurats were not places for public worship or ceremonies as they were believed to be dwelling places for the gods and each city had its own patron god. Only priests were permitted on the ziggurat or in the rooms at its base, and it was their responsibility to care for the gods and attend to their needs. The Mesopotamians believed that these pyramid temples connected heaven and earth. The later ziggurat at Babylon was known as Etemenankia or “House of the Platform between Heaven and Earth”.. Unfortunately, not much of even the base is left of this massive structure, yet archaeological findings and historical accounts put this tower at seven multi-coloured tiers, topped with a temple of exquisite proportions. The temple is thought to have been painted and maintained an indigo colour, matching the tops of the tiers. It is known that there were three staircases leading to the temple, two of which were thought to have only ascended half the ziggurat’s height.