 It is the largest county in Minnesota and the largest (by total area) in the United States east of the Mississippi River.Voyageurs National Park, established in 1975, is located in its northwestern corner, on the south shore of Rainy Lake on the Canada–US border; it is popular with water enthusiasts and fishers.The county includes parts of Superior National Forest, established in 1909, and the Boundary Waters Canoe Area Wilderness on the border, established in 1978.