Stepped pyramid

A step pyramid or stepped pyramid is an architectural structure that uses flat platforms, or steps, receding from the ground up, to achieve a completed shape similar to a geometric pyramid. Step pyramids are structures which characterized several cultures throughout history, in several locations throughout the world. These pyramids typically are large and made of several layers of stone. The term refers to pyramids of similar design that emerged separately from one another, as there are no firmly established connections between the different civilizations that built them.

Ziggurats were huge religious monuments built in the ancient Mesopotamian valley and western Iranian plateau, having the form of a terraced step pyramid of successively receding stories or levels. There are 32 ziggurats known at, and near, Mesopotamia. Twenty-eight of them are in Iraq, and four of them are in Iran. Notable Ziggurats include the Great Ziggurat of Ur near Nasiriyah, Iraq, the Ziggurat of Aqar Quf near Baghdad, Iraq, Chogha Zanbil in Khūzestān, Iran, the most recent to be discovered – Sialk near Kashan, Iran and others. Ziggurats were built by the Sumerians, Babylonians, Elamites and Assyrians as monuments to local religions. The probable predecessors of the ziggurat were temples supported on raised platforms or terraces that date from the Ubaid period during the fourth millennium BC, and the latest date from the 6th century BC. The earliest ziggurats probably date from the latter part of the Early Dynastic Period of Sumer. 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. Kings sometimes had their names engraved on these glazed bricks. 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. It was also called Hill of Heaven or Mountain of the gods.

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