I know there are some wonders that modify the amount, but what I'm really looking for is information on what factors determine how much each tile costs, since they seem to vary per-tile and over time (and/or if you purchase tiles).
In my experience, the factors which effect purchase cost are:
- Current turn/era (the later the costlier)
- Number of tiles the city already has (the larger the costlier)
- Distance from the city (the further away the costlier)
- Whether the tile is one which is considered for expansion - i.e. has a purple border (if it is, it's about half the price)
For a more complete reference, below is the section from the game configuration file which deals with "acquiring new plots", as it is called there. Any entry with "culture" applies to culture "cost" only, but I'm not quite sure what the entries with "influence" mean; perhaps this applies to both gold and culture cost.
(the section was originally in XML format, but I've changed it to something friendlier)
Cost of acquiring new Plots PLOT_BASE_COST = 50 PLOT_ADDITIONAL_COST_PER_PLOT = 5 PLOT_COST_APPEARANCE_DIVISOR = 5 CULTURE_COST_FIRST_PLOT = 15 CULTURE_COST_LATER_PLOT_MULTIPLIER = 10 CULTURE_COST_VISIBLE_DIVISOR = 5 CULTURE_PLOT_COST_MOD_MINIMUM = -85 MINOR_CIV_PLOT_CULTURE_COST_MULTIPLIER = 150 MAXIMUM_BUY_PLOT_DISTANCE = 3 MAXIMUM_ACQUIRE_PLOT_DISTANCE = 5 PLOT_INFLUENCE_DISTANCE_MULTIPLIER = 100 PLOT_INFLUENCE_RING_COST = 100 PLOT_INFLUENCE_WATER_COST = 25 PLOT_INFLUENCE_IMPROVEMENT_COST = -5 PLOT_INFLUENCE_ROUTE_COST = 0 PLOT_INFLUENCE_RESOURCE_COST = -105 PLOT_INFLUENCE_NW_COST = -105 PLOT_BUY_RESOURCE_COST = -100 PLOT_BUY_YIELD_COST = 10 PLOT_INFLUENCE_YIELD_POINT_COST = -1 PLOT_INFLUENCE_NO_ADJACENT_OWNED_COST = 1000
Thanks for the answer! I have noticed some of these factors over time as well, but am glad to see them in one place. I wonder if the game developers expose any of this logic, or if it's all compiled in...– Dan FegoMay 1, 2012 at 20:50
@DanFego some of the logic is exposed, though not always clear - I've added it to the answer.– OakMay 1, 2012 at 21:02
Wow thanks! I wish I could double-upvote!– Dan FegoMay 1, 2012 at 21:04
3The number of tiles bought by your civ (in any town) is also taken into account. Each purchase increases costs.– dgwMay 2, 2012 at 13:45