means steps to heaven they were built by ancient Sumerians, Akkadians, Assyrians, Elamites, Eblaites and Babylonians for local religions, predominantly Mesopotamian religion and Elamite religion. Each ziggurat was part of a temple complex which included other buildings the ziggurat was a mastaba-like structure with a flat top. The sunbaked bricks made up the core of the ziggurat with facings of fired bricks on the outside. Each step was slightly smaller than the step below it. 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 floors ranged from two to seven. According to archaeologist Harriet Crawford, "It is usually assumed that the ziggurats supported a shrine, though the only evidence for this comes from Herodotus, and physical evidence is nonexistent. It seems reasonable to adopt as a working hypothesis the suggestion that the ziggurats developed out of the earlier temples on platforms and that small shrines stood on the highest stages.

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. 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 priests were very powerful members of Sumerian and Assyro-Babyloniansociety. One of the best-preserved ziggurats is Chogha Zanbil in western Iran. The Sialk ziggurat, in Kashan, Iran, is the oldest known ziggurat, dating to the early 3rd millennium BCE Ziggurat designs ranged from simple bases upon which a temple sat, to marvels of mathematics and construction which spanned several terraced stories and were topped with a temple. So far, 11 ziggurat have been discovered from historical sources and 21 ziggurats by archaeological excavations. Some of these ziggurats which are located in Iran are:

1: Kashan Sialk Ziggurat:

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

2: Chogha Zanbil Ziggurat:

Located in the southwestern part of Iran, close to the city of Shush, it is the safest residual ziggurat in the world, and dates back to 1250 BC. The Chogha Zanbil building is located in the middle of this city and its highest part. This sanctuary was built by Ontash of Napier about 1250 BC, the king of the Great Elamite, and praised by the god Ishushinak, the guardian goddess of Shush (ancient city); which was attacked by the army the assassination of Assyrian Banipal and was destroyed along with Elamite civilization.

3: The Susa Ziggurat:

Belonging to the ancient Elamite about 3800 years ago, has now been destroyed and its historical information has come to our attention. Sandal Ziggurat of the Jiroft has been recently discovered and is older than Chogha Zanbil ziggurat. This ziggurat belonged to the Arta people, and the archaeological excavation has not yet been completed.

4: The haft-Tapeh ziggurat:

Based on the research of the doctor Negahban it, belongs to the Middle Elamite period and was built in 1357 B.C.