The plain in the old lakebed provided a low-grade but very swampy overland route across the divide between the East and West Savanna Rivers. Wolf Lake, source of the East Savanna River, is only about east of Savanna Lake on the West Savanna. As Wolf Lake and the upper East Savanna River are quite wet, the route selected for the portage trail departed from the river further downstream, shortening the distance to be traveled through the bog. The portage, some long, starts in the swamp and then goes west in a wooded upland to reach the West Savanna River.