Masjid Al Khulafa' (The Caliph's Mosque) in Baghdad, Built during the Abbasid era
<a href="//commons.wikimedia.org/wiki/User:Aziz1005" title="User:Aziz1005">aziz1005</a>
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span>