Agassiz National Wildlife Refuge is located in northwest Minnesota. Packs of wolves, moose, waterfowl, and 280 species of birds make this refuge a wildlife wonderland. The refuge, originally named Mud Lake Migratory Waterfowl Refuge, was established in 1937 primarily for waterfowl production and maintenance. Located in eastern Marshall County, the contiguous 61,500 acres are situated in the aspen parkland region of northwest Minnesota. In 1976, 4,000 acres of the refuge were designated a Wilderness Area. Each year over 20,000 visitors enjoy wildlife viewing on Agassiz Refuge's self-guided auto tour route and hiking trails. Today, Agassiz is composed of 40,100 acres of wetlands, 10,000 acres of shrublands, 7,000 acres of forestland, 4250 acres of grassland, and 150 acres of cropland. The Wilderness Area encompasses one of the most westerly extensions of black spruce-tamarack bog in Minnesota. Two lakes in the area were formed by deep peat fires which occurred prior to settlement of the area.