Civilization IV/Other mods
 City range
The default minimum city range, or minimum city distance, is 2 squares between cities. Some mods change this to 3 squares to lessen overlap between cities. This distance can be changed by editing the file GlobalDefines.xml in the directory Sid Meier's Civilization 4\Assets\XML. (Search for "MIN_CITY_RANGE".) To make this change in a mod rather than your main files (which should always be backed up), edit GlobalDefinesAlt.xml in the directory Mods/[Mod name]/Assets/XML/.