This is a pencil drawing of the fortress in Belgrade, Serbia.
The gate shown on the left hand side of this picture is a Turkish style architecture whilst the Orthodox church attached to this fortress is an European style. This whole architectural design represents the history of Balkans where the long history of various conflicts between the Eastern Europe (Serbia and surroundings) and the Islamic empires (Such as Osman Turkish empire), and the West Europe (such as with Austria-Hungary empire under Hapsburg dynasty) although Hapsburg armies could hardly reach this fortress due to the tremendous difficulty to conquer this fortified fortress located on the top of hill.