Throughout history, especially in prehistoric and early history, castles have played an important role in the fortification of Iran. They were usually maintained by officials on important routes or cities, and most of them were in unmarked heights with steep slopes or cliffs. Such places have always served as a natural defenses against enemies and offer a panoramic view of the surrounding lands, so cities and surrounding lands can be defended. Most of Iran's castles had spring or Wells, except for those that were previously surrounded by water.