The Hukou Waterfall.[Photo by Khalid Sharif/For chinadaily.com.cn]

The next day, we boarded our bus to continue our journey. This time our destination was the Hukou Waterfall, the largest waterfall on China's Yellow River.

When we got close to the falls, I saw a breathtaking view of the river and the roaring of the water frightened me.

Hukou is where water from the middle reaches of the Yellow River flows through Jinshan Grand Canyon. Just below the waterfall is a shining stone called guishi (turtle stone).

What makes the stone mysterious is that it moves up and down according to the water level. No matter how large the water volume, it is still at least partly visible.