Bâb-ı Hümâyûn, first of the three ceremonial gates of Topkapı Palace, built in 1478 by Sultan Mehmet the Conqueror, is the entrance to the first courtyard. Originally it was built on a rectangular plan, a two-storey symmetrical structure with a vaulted section between the exterior and interior sides. This section recalls the monumental portals of medieval castles; the two niches on either side are reminiscent of Seljuk structures. The upper floor (royal lodge) was used by the sultan to observe various ceremonies and pageants. Inscribed in marble on the interior and exterior facades, the Koranic verses, the imperial signature (tuğra) of Sultan Abdülaziz and an Arabic inscription signed by Ali b. Yahya es Sufi are dated 1478.
Scholars of Our country will tell about Yavuz Sultan Selim and Sacred Relics at date December 14th Thursday 13:00 in Topkapı Palace with participation of Governor of Istanbul Vasip Şahin with cooperation of İstanbul Directorate of Culture and Tourism and Municipality of Üsküdar