Rail, road and the last part of the journey
A useful connection takes you to the right place, not merely the right name on a map.
Three valleys with different kinds of days, from shuttle-assisted sightseeing to longer mountain walks.

Shuangqiao is the most developed of the three visitor valleys, with scenic transport and stops among mountain and forest scenery. It is the natural starting point when your priority is views rather than a long trek. Decide which walks to add between stops according to current access and your energy; using a shuttle does not make this a low-altitude outing.
Changping offers a different approach through forest towards mountain scenery. Set a return point that matches your daylight, walking pace and the open route. Do not assume that walking into the valley authorises a through-trek to another region. Ask separately about registration, guiding and equipment if your plan extends beyond the ordinary visitor route.
Haizi is another valley with its own entrance and ticket arrangements. A scenic-area admission and a mountain-climbing arrangement are different things. Be specific about whether you want a short walk, a longer hike or a summit attempt, then confirm the corresponding rules and provider qualifications. Do not use a sightseeing itinerary as a summit route description.
Siguniangshan town is a useful accommodation base, but check the exact hotel location against your valley entrance. Ask about heating, meals, luggage storage and the morning transfer. With two visiting days, choose valleys that suit the group rather than adding all three by default. Allow the road journey from Chengdu and the first night at altitude their own time.
A useful connection takes you to the right place, not merely the right name on a map.
Check what applies to your passport, your travel dates and the exact place you will visit.
The right neighbourhood can save more travel time than a longer list of hotel amenities.
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