Only about 80 miles from Butler Creek Lodge, Flathead Lake is worth the trek. It is the largest natural freshwater lake west of the Mississippi in the lower 48 states, with over 200 square miles of water and 185 miles of shoreline. The southern half of Flathead Lake is within the boundary of the Confederated Salish and Kootenai Tribes Flathead Reservation and recreationists must purchase a tribal recreation permit in this area.

Recreation on and around the lake includes: sailing, power boating, waterskiing, swimming, fishing, picnicking, and camping. In the summer, roadside stands along the east shore offer a variety of locally grown cherries, apples, plums, and other fruits. There are numerous motels and rental cabins, in addition to public campgrounds scattered all around the shoreline. The major population centers around the lake are Kalispell, Bigfork, and Polson, all of which offer a complete variety of groceries, supplies, and information.