The Walls of Constantinople AD 324–1453

The Theodosian walls were pierced by ten main gates and several small postern gates. Postern gates were few in number for security reasons and almost all were located in the inner wall. The main gates can be divided into two types: the military gates that led to different parts of the fortifications and the public gates that were the entrances to the city by means of bridges across the moat. The two series followed each other in alternate order, the military entrances being known by numbers and the public gates by proper names. Both the public and the military gates shared a common overall design. All were double gateways because they had to pierce two walls. The inner gateway, being the principal one, was built into the Inner Wall of the Theodosian line. Two large towers that projected far beyond the curtain wall guarded all the gateways. The towers were of very similar design to the towers found along the length of the walls as described above. The Belgrade Gate provides an excellent example of this, showing how the projecting walls would allow defenders to achieve good flanking fire and to protect the outer gateway by archery. The other intention behind the design was that the distance across the peribolos between the two sets of gates should be made deliberately as narrow as possible. By contrast, the gates in the Outer Walls were quite modest affairs, consisting of a simple gated arch not much higher than the Outer Wall level.