Dakota County, Minnesota, has recently completed a development plan for a 20-mile regional trail along the Mississippi River. GIS played an important role in the creation of the plan. Planners used contours and physical feature data (buildings, railroad tracks, driveways, etc.) to identify an initial route through the river valley's rugged terrain. Wetlands, poor soils, and environmentally sensitive areas were mapped and avoided. Scenic vistas were identified using terrain analysis. Property ownership queries were used to notify and involve citizens in the planning process. While planning for the trail, a number of complex issues and concerns became readily apparent. GIS provided County planners with the tools and information to effectively address these issues and concerns.