As a civilization grows, it requires an ever-larger infrastructure to support it. Entire new layers of bureaucrats appear to handle the increasingly complex business of empire. And with every new layer of bureaucracy comes new inefficiencies, as well as increased opportunities for corruption. In Civilization IV, this is reflected in your civilization's "city maintenance cost."
Two factors determine a civilization's basic city maintenance cost: the number of cities you possess, and the distance of individual cites from a seat of government.
Number of Cities
As you add cities to your civilization, the cost of managing EVERY city increases. Thus, as your civilization grows, adding new cities will quickly drive up your city maintenance costs. For instance, let's assume that the first city costs one gold to manage, and every new city increases the cost of managing your cities by one. So you pay one gold in management expenses when you have one city. When you build another city, you are now paying two gold PER city, so your overall costs goes up to four. Adding a third city will increase your maintenance costs to nine, and so on. (Note that these numbers are for example only; the actual formula for determining maintenance is more complex.)
Distance from Seat of Government
A city's maintenance cost is also affected by its distance from a "seat of government." At game start the Palace, which appears automatically in the first city you build, is your seat of government. Cities farther away from the palace are more expensive to maintain than closer cities.
Lowering Maintenance Costs
- Courthouses - Building a Courthouse cuts a city's maintenance cost in half. Courthouses are also required to build the Forbidden Palace national wonder (see below). If your civ finds itself choking under high maintenance costs from expanding too far afield, make sure to build courthouses as quickly as possible.
- Move Your Palace - If your palace is out on the edge of your civilization, you can construct it in a more centralized position. Warning: the original palace disappears when the new one appears.
- Add Seats of Government - Two wonders, the Forbidden Palace and Versailles, act as additional seats of government. Cities pay maintenance based upon their distance to the NEAREST seat of government, so spreading these about your empire will do wonders for lowering your maintenance costs. Although the Forbidden Palace is a National Wonder and always available to your civ, be aware that only one civilization in the world will be able to construct Versailles.
- State Property - The State Property civic removes all distance-based maintenance costs.
Make More Money!
You can, of course, counter the rising costs of city maintenance by simply making more money. See Wealth for further suggestions.