Using them all will considerably increase your defense potential and will allow you to defend your air space. In this case, there only are 5 slots available. It is best to take interest in this structure at the beginning of a war, when demand for aviation increases. What makes it an important thing is that small amount of air bases can quickly result in them being overstaffed, which both decreases their effectiveness and promotes accidents, where you lose many units. Thanks to using several air bases, you can increase the limit of units available for production. Time required to organize infrastructure is short and in the case of enemy aggression, you can deploy your forces on many fronts at the same time. At the beginning of the game, development of infrastructure is not the key matter, but in the long run, you should reach the limit cap for each of the regions. Thanks to the proper development of infrastructure, you can deploy your armies around your territory faster and you can be sure that your army will not run out of supplies. This structure is important for all the actions that you want to perform on your own territory. In each region, you can erect only a specific number of these, without worrying about available space. The below structures have their own level of development that has been predefined by the game creators.