(4) The Alai Darwaza, the maingateway from southern side ofthe Quwwat-ul-Islam Mosquein the Qutb Minar complex,was the first building in Indiato employ Islamic architectureprinciples in its constructionand ornamentation. It wasbuilt by the second Khalji Sultanof Delhi, Alauddin Khaljiin 1311 AD. The domed gatewayis decorated with red sandstoneand inlaid white marbledecorations, inscriptions inNaskh script, and latticedstone screens.It is also notedfor the use of horseshoe archand true dome for the firsttime.