It is one of the most important initiatives of sorrow.
Since the Byzantine period cities were surrounded by walls, the same order prevailed in iznik.
In addition, the entrance gates of these cities are of serious importance, the gates are made more imposing than those against big cities and countries, with more care.
There are also two doors in Iznik that are very special, one facing the Bilecik side and the other facing the Istanbul side.
But the most special and most carefully made of these two special doors is the Istanbul Door