0.7 miles, +750 feet, 5.2 mile approach
Rock Island Butte is in the southern portion of the Absoraka-Beartooth Wilderness. We climbed it from the Chief Joseph Trailhead as part of an extended backpacking trip, but it is also reasonable to climb it as a day-hike. If camping overnight, there is an excellent isolated campsite on the south side of Widewater Lake near where the trail dips closest to the lake. There are also numerous campsites in the Widewater-Big Moose area.