I would like to ask how to plan the route without going back to Chongqing, Zhangye, Dunhuang and Qinghai Lake.

Hello, I'm Master Jiang from Dunhuang Tourist Bus. Your route can be determined as follows: 1. As you said, Chongqing will go to Lanzhou, from Lanzhou to Zhangye via Wuwei, and see Zhangye Buddha Temple and colorful Danxia, then Jiuquan and Jiayuguan will go to Dunhuang, and Dunhuang will see the Mogao Grottoes, Crescent Moon Springs and Ya Dan landforms. From Dunhuang to Delingha via Aksai and Dachaidan, from Delingha to Qinghai Lake via Wulan Chaka, Qinghai Lake to Xining and Xining to Chongqing. It's nearly 3000 kilometers to walk in a big circle like this. It's too tired. If you mainly go to Zhangye, Dunhuang and Qinghai Lake as you said, you can choose Chongqing to fly directly to Dunhuang (if there is no direct flight, you can transfer at Lanzhou, and the plane from Lanzhou to Dunhuang is discounted. 1000 kilometers costs more than 200 yuan). We can go back from Dunhuang, pass Jiayuguan to Zhangye, cross Qilian Mountain from folk music, and return to Chongqing from Xining after swimming.