Ziggurat means the road to heaven, they were built by the ancient Sumerians, Akkadians, Assyrians, Elamites, Eblaites and Babylonians for the local religions, mainly the Mesopotamian religion and the Elamite religion.

Each Ziggurat was part of a temple complex that included other buildings, the Ziggurat was like a mastaba with a flat top. Sun-baked bricks formed the core of the Ziggurat, with a baked brick cladding on the outside. Each step was a little smaller than the step below him. The facings were often glazed in different colors and may have had astrological significance. Kings sometimes engraved their names on these glazed bricks. The number of floors varied from two to seven.
Access to the sanctuary would have been through a series of ramps on one side of the Ziggurat, or along a spiral ramp from the base to the top. Mesopotamian Ziggurats were not places of public worship or ceremony. They were considered the habitats of the gods, and each city had its own patron god. Only priests were allowed on the Ziggurat or in the rooms within its base, and it was their duty to care for the gods and attend to their needs. Priests were very influential representatives of Sumerian and Assyro-Babylonian society. One of the best preserved Ziggurats is Chogha Zanbil in western Iran. The Sialk Ziggurat in Kashan, Iran is the oldest known Ziggurat, dating back to the early 3rd millennium BC. Ziggurat designs ranged from simple foundations on which the temple sat, to marvels of mathematics and construction that spanned several terraced stories and were crowned by a temple.
To date, archaeological excavations have discovered 11 Ziggurats out of 21 Ziggurats according to historical sources. Here are some of these Ziggurats that are found in Iran:

1. Kashan Sialk Ziggurat:

The manufacturer of this Ziggurat is not specified, but the date of construction is 2500 BC. Sialk Hill was actually a sanctuary of the ancient people, made of clay and pottery. This historical complex was not identified by 1310 and was known among the inhabitants of Kashan as a cursed city.

2. Choga Zanbil Ziggurat:

Located in the southwestern part of Iran, near the city of Shush, it is the safest remnant Ziggurat in the world and dates back to 1250 BC. The Choga Zanbil building is located in the center of this city and its highest part. This sanctuary was built by Ontash of Napier around 1250 BC, king of the Great Elamite, and was praised by the god Ishushinak, the guardian goddess of Shusha (ancient city); which was attacked by the army while killing the Assyrian Banipal and was destroyed along with the Elamite civilization.

3. Ziggurat Kenar Sandal:

Belonging to the ancient Elamites about 3800 years ago, it is now destroyed, but its historical information has attracted our attention. The Sandal Ziggurat of Jiroft was recently discovered and is older than the Ziggurat of Choga Zanbil. This Ziggurat belonged to the Arta people and the archaeological excavations are not yet completed.

4. Ziggurat Haft Tapeh:

According to the research of Dr. Negahban, it dates back to the Central Asian period and was built in 1357 BC.

Source: Aria Dokht

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