The Imperial Gate of the Topkapi Palace in Turkish is called Bab- i Humayun. This is the outer most gate in the Topkapi Palace, beside the Sultan Ahmed III Fountain. This massive gate opens into the First Courtyard. The Gate was built in 1478 during the Sultan Mehmed II (the Conqueror) era, it is now covered in 19th-century marble.
There is an inscription in Arabic by Ali ibn as-Sufi, which reads as follows: “By the grace and assent of God and with the aim of establishing peace and tranquility. This auspicious citadel was built and erected in the blessed month of Ramadan in the year 883 [November-December 1478] at the command of the son of Sultan Murad, son of Sultan Mehmed Khan, the sultan of the lands and the emperor of the seas, the shadow of God extending over men and djinn, the deputy of God in the East and in the West, the champion of the water and the land, the conqueror of Constantinople and father of that conquest Sultan Mehmed, may God make his reign eternal and exalt his abode above that of the highest stars in the firmament.”