Plains are open areas that differ from Grassland in having poorer soil but better resources of timber and minerals. They are poor food producers unless irrigated. Due to the presence of resources and the automatic irrigation a new city gets, they make good choices for city sites. Plains may be converted into forests by Settlers.
Plains produce 1 food and 1 resource. Horses can be found on plains, generating an extra 2 resources (and another with Railroad).
It costs 1 Movement Point to travel onto a Plains region.