Everybody might have seen a picture of the big ancient building before which have sanctuary on the top. Many people misunderstand and though it's a pyramid. In reality, it's a lot bigger. Ziggurat is a Sumerian's building which builds for worship god. Mostly used to perform the ritual. They usually have a parade around the town and end with Sacrifice at the top of the ziggurat. Then, God belief was forgotten. Ziggurat became a part of the palace.
Ziggurat was built from the brick and wood so it doesn't sting like Egypt's pyramid. The oldest ziggurat is "The white temple" located at Uruguay, Iraq. Estimated age 3500-3000 BC.Older than the Pyramid of Eypt many hundred years.