BC.

The earliest ziggurats began near the end of the Early Dynastic Period. The original pyramidal structure, the anu ziggurat, dates to around 4000 BC. The White Temple was built on top of it circa 3500 BC. 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