A wilderness is any area on the map that is not a city. There are 7 types of wildernesses: lakes, swamps, forests, barrens, uplands, pastures and plains. Wildernesses are ranked on a 0-10 scale with 0 being of least value, and 10 being the greatest. Wildernesses can be scouted, marauded , and captured just like any hostile city. Captured wildernesses increase production of a resource, and can be gathered for resources and jewelry. Once a wilderness has been captured, its level is reduced on a daily basis until it reaches zero.
Capturing wildernesses increases the production of a resource. Lakes and pastures increase food production, forests increase lumber production, barrens increase stone production, and uplands increase iron production. Plains do not increase any resource production, but can have cities built on them.
Resource production increases with level.