From Ashton, Idaho, the Mesa Falls Scenic Byway heads northeast into the lush landscape of the Targhee National Forest. It’s a loop that runs for nearly thirty impressive miles all the way to the Island Park area. This byway includes the popular Warm River campground and two of the most spectacular waterfalls in the West — lower and upper Mesa Falls. At the upper falls you can stop at the historic Big Falls interpretive center to learn about the geology and history of the area.