High Quality Content by WIKIPEDIA articles! A sahn , in Islamic architecture, is a courtyard. As per the traditional Islamic architectural style, almost every mosque has a sahn, which is surrounded by an arcade from all sides. In Persian architecture, the sahn usually contains a howz, a symmetrical pool, where ablutions are performed. Some also contain drinking fountains. The use of the sahn is very old, ruins of houses in Ur with sahns have been found. It is probably the unifying element in almost all buildings throughout the Arab world from Iraq to Morocco; used in urban, rural and Bedouin communities. Originally, it was used for residential buildings, mainly houses and palaces, as a private internal garden; later on it was used for every building.