Citadel

The citadel is the primary building in your city and determines your city's current level. Much of what you can do in your city is determined by the current level of your citadel. As your citadel levels up you can purchase additional land, build new structures, upgrade existing structures, and erect statues. The maximum level of most structures in your city will match the current level of your citadel.

Starting at level 10, when your city is plundered in battle your citadel will lose durability and will catch on fire, which slowly depletes durability further. Durability can be instantly restored using crystals or restored slowly by visiting the citadel and repairing it every 30:00. If the citadel reaches zero durability, it will lose the area of influence of the city and that of the alliance. The city itself may also teleport on the map if it is attacked again once at zero durability.

The citadel also displays to the player a lot of information to the player in the Defense and Statistics tabs, including information on castle durability, city resources, a list of structures, and all kinds of bonuses from VIP level, research, items, boosts, etc.