Changping Valley is the longest and least developed of the three main valleys, 29 kilometres from entrance to the high-altitude terrain above the treeline. No vehicles are permitted, which means the only way in is on foot, and the absence of buses and tarmac immediately distinguishes the experience from Shuangqiao. The six-kilometre boardwalk through old-growth spruce and fir forest establishes the valley's character: dark, cool, and dense, with bird calls that travel further than they would in thinner forest.
Beyond the boardwalk, the path climbs through open meadows and stream crossings toward the upper cirques where the terrain becomes alpine. The valley's western face gives direct views of Yaomei Peak, the second of the four Siguniang summits. A day is enough to do the boardwalk and return; seeing the upper valley properly requires camping or the small guesthouse near the boardwalk's end. The entrance to Changping Valley is about two kilometres from Rilong town.