The Great Mosque is located in the center of the city of Şanlıurfa. It was built in the place of an old church called the “Red Church.” The courtyard walls, columns, column heads, and the bell tower in the old building are still present. It is estimated that the mosque was built between 1170-1175 AD. After the Islamic conquests, it was called the "Red Mosque" because of the red marble used in construction. The mosque opens onto a courtyard surrounded by fourteen pointed arches, each covered with cross vaults.