Dujiangyan and Mount Qingcheng.

Dujiangyan is a miracle of ancient Chinese water conservancy engineering and a UNESCO World Heritage Site. During the Qin Dynasty, Li Bing and his son used the principle of thrust to divert the Min River. They used bamboo baskets filled with cobblestones to build a dam and iron pillars to divert the river. The Min River was divided into two parts, one for irrigating farmland and the other for flood discharge (later used for power generation). It can be said that this project was the first of its kind in the world. Mount Qingcheng is beautiful and secluded, with mountains, lakes, pavilions, and temples all connected. The winding paths are full of mysteries. The first time I went to Mount Qingcheng, I went down the wrong mountain and ended up on Yangren Street. I had to take a taxi back to the group. Dujiangyan and Mount Qingcheng can be arranged as a one-day tour. The local travel agencies in Chengdu are the most enthusiastic and thoughtful, and the prices are reasonable. Don't drive yourself, it's a hassle.