The quality and Formation of Tombs

There exist some theories about the formation and evolution of tombs in Islamic world, that prove the origin of tombs come from lands other than Iran. It seems that there it hasnt done enough studies and researches by the Iranian researchers in this regard.This paper aims at surveying some of the theories and produces a new theory in this case and also surveying the architectural formation of tombs in Iran. The main questions in this research are: 1) What and where has been the origin and pattern formation of tombs?2) How has been the process of tombs transformation in Iran?The hypothesis in this research is: The "Tchahar Tag" (quadric arch) was the origin of dome form of Tombs and then some the other forms with a dome in Iran and the Islamic world. The Theoretical framework of this research is that the tomb is a type of space among other architectural spaces, wherein cultural Phenomenon has an effective role in Tombs formation. The historical- interpretational method was used in this research and the data was collected through documentary and field study methods.The results of this research indicate that the first designed and magnificent tombs were built in Iran and its forms rooted from quadri arch and domes.