1. The earliest train from Chengdu to Zhenjiang Pass is 7:30-08:59.
   
2. Zhenjiang Pass is closer to Huanglong, so you can go to Huanglong first.
   
3. Huanglong-
   Jiuzhaigou Valley
   , there is a bus, the latest is 18:30. If you can’t make it in time, there are buses to the airport.
   Jiuzhaigou Valley
   , the latest time is 23:00.
   
4. Go the next day
   Jiuzhaigou Valley
   , if you take the bus to the scenic spot, you can spend a day there.
   
5. Ruoergai Grassland, Huanglonghe
   Jiuzhaigou Valley
   There are no buses. If you want to drive, Huanglong drive takes 3 hours and 24 minutes, 204 kilometers.
   Jiuzhaigou Valley
   It took 4 hours and 40 minutes to drive, 283 kilometers. If you don’t have a bus, you still need to drive from Ruoergai to Zhenjiangguan, which takes 3 hours and 40 minutes, 241 kilometers.
   
6. Huang Longhe
   Jiuzhaigou Valley
   They are all places with a higher altitude. If the altitude is high, it is not recommended to visit for too long, nor is it recommended to drive by yourself.
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