The longest of the three main valleys in the Four Sisters Mountain area is also the most accessible to tourists, with a wooden boardwalk that runs for about 30km of the valley's 40km length, and regular shuttle buses running throughout the day. Shuttle tickets are ¥70, not including the 7km transfer from Rilong, but if you want to get to the most impressive scenery at the far end of the valley it's the only way to do it in a day.
The valley receives a lot of groups of selfie-stick welding Chinese package tourists, and the lower ends of the valley or the areas near where the shuttle drops people off can be oppressively busy.