JiuZhaiGou trip from Chong Qing

You need to take a high speed train to Chengdu first, then take another high speed train from Chengdu to Zhenjiangguan Railway Station where you can take a direct bus to Jiuzhaigou. Since you arrive in Chongqing at 1:15am, you will need to stay overnight in Chongqing as all the transportation to the train stations stop that time.