Persian Architecture, Iran

Available building materials dictate major forms in traditional Iranian architecture. Heavy clays, readily available at various places throughout the plateau, have encouraged the development of the most primitive of all building techniques, molded mud, compressed as solidly as possible, and allowed to dry. This technique used in Iran from ancient times has never been completely abandoned. The abundance of heavy plastic earth, in conjunction with a tenacious lime mortar, also facilitated the development of the brick.
Geometry
Iranian architecture makes use of abundant symbolic geometry, using pure forms such as the circle and square, and plans are based on often symmetrical layouts featuring rectangular courtyards and halls.