Iznik pottery
The ceramic collection of the Topkapi Palace includes over ten thousand pieces of Chinese porcelain but almost no Iznik pottery. Most of the surviving Iznik vessels are in museums outside Turkey, but examples of the city's tile production exist in numerous cities throughout Turkey, such as İstanbul, Bursa, Edirne and Adana. In Istanbul examples of Iznik tiling can be seen in mosques, tombs, libraries, and palace buildings, such as the Rüstem Pasha Mosque, the Sokollu Mehmet Pasha Mosque, the tomb of Selim II in the Hagia Sophia complex, and certain buildings of the Topkapı Palace complex such as the Circumcision room and the Baghdad Kiosk.
Topkapı Palace
The Imperial Gate is the main entrance into the First Courtyard. The sultan would enter the palace through the Imperial Gate ( or "Saltanat Kapısı") located to the south of the palace. This massive gate, originally dating from 1478, is now covered in 19th-century marble. Its central arch leads to a high-domed passage; gilded Ottoman calligraphy adorns the structure at the top, with verses from the Qur'an and tughras of the sultans. The tughras of Mehmed II and Abdül Aziz I, who renovated the gate, have been identified.