The Alai Darwaza is the main gate from the southern side of the Quwwat-ul-Islam Mosque in the Qutub Minar complex .Built by Allaudin Khilji the Sultan of Delhi in 1311 AD, the Alai Darwaza has a domed entrance which is constructed using red sandstone and is adorned with white marble. 
<a href="//commons.wikimedia.org/w/index.php?title=User:Romit_Dasgupta&amp;action=edit&amp;redlink=1" class="new" title="User:Romit Dasgupta (page does not exist)">Romit Dasgupta </a>
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<span class="int-own-work" lang="en">Own work</span>