Ziggurats were built by the Sumerians, Babylonians, Elamites and Assyrians of ancient Mesopotamia as monuments to local religions. The earliest examples of the ziggurat were raised platforms that date from the Ubaid period during the fourth millennium BC, and the latest date from the 6th century BC. The top of the ziggurat was flat, unlike many pyramids. The step pyramid style began near the end of the Early Dynastic Period. Built in receding tiers upon a rectangular, oval, or square platform, the ziggurat was a pyramidal structure. 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 astrological significance. The number of tiers ranged from two to seven, with a shrine or temple at the summit. Access to the shrine was provided by a series of ramps on one side of the ziggurat or by a spiral ramp from base to summit. Notable examples of this structure include the Great Ziggurat of Ur and Khorsabad in Mesopotamia.






Great Ziggurat of Ur

 The Ziggurat was dedicated to the moon god Nanna (or Suen; The name Nanna is Sumerian for "illuminator") in the Sumerian city of Ur in ancient Mesopotamia, in present-day Iraq, near Nasiriyah south of Baghdad. The construct, a huge stepped platform, was built approximately in the 21st century BC by King Shulgi. In Sumerian times it was called Etemennigur. Today, after more than 4000 years, the ziggurat is still well preserved in large parts, and partially reconstructed, as the only major remainder of Ur in present-day southern Iraq. Its upper stage is over 100 feet (30 m) high and the base is 210 feet (64 m) by 150 feet (46 m).

The ziggurat was a piece in a temple complex that served as an administrative center for the city, and which was thought to be the dwelling of the moon god Nanna, the patron deity of Ur, on earth. Temples and shrines are built on top of the trapezoidal base. It is said that ziggurat serves as a tool to bridge the distance between the sky and the earth. The gods are believed to descend and visit the temple where only a selected group of priests and government officials may enter. The construction of the ziggurat was finished in the 21st century BC by King Shulgi, who, in order to win the allegiance of cities, proclaimed himself a god. During his 48-year reign, the city of Ur grew to be the capital of a state controlling much of Mesopotamia. Later though, the fortunes of Ur declined, and it was sacked by the Elamites.