61 60 Cities can either be building an improvement or training a unit at anyone time. The improvement being worked on, or unit being trained, at any given time is indicated by the first item in that city’s build queue. Every season, all of the Production of that city will be applied toward that item in an effort to finish its construction. You can queue up later improvements or units to be worked on upon the first item’s completion. You can adjust the order of items in the queue by dragging and moving them on the city info panel of the main UI, though you cannot rearrange them on the city details screen. Because you can only have a single unit or improvement underdevelopment in a city at a time, deciding when you should improve your economy versus when you should strengthen your military is of the utmost importance.