United States, Illinois, Vermilion, Vermilion River Section of the Wabash Border Natural Division of Illinois. Collison 7.5 minute quadrangle. About 3 mile directly east of town of Collison & in and along, floodplain and adjacent upland woods, east side of the Middle Fork of the Vermilion River. Elevation about 600 feet. UTM Zone 16, 435507mE, 4453164mN.