The largest island in the largest freshwater lake (Flathead Lake) west of Minnesota. Wild Horse Island has been a landmark since the Salish-Kootenai Indians were reported to have used it to pasture horses to keep them from being stolen by other tribes. The park is noted for its wildlife including bighorn sheep, mule deer, songbirds, waterfowl, bald eagles, and falcons, as well as five wild horses. Rare and endangered plant species have also been found on its Palouse Prairie grasslands. The island's scenic shoreline is a favorite of hikers, boaters, swimmers and sailboat enthusiasts. Day-use only is allowed, and there are other strict rules to ensure maintenance of its natural character. There is a composting toilet at Skeeo Bay.