How was the Great Wall built upside down?

The "upside down Great Wall" scenic spot is located eight kilometers northeast of Shanhaiguan. Sandaoguan is the three passes of the Great Wall to resist foreign invasion, and the Great Wall is upside down.

There is a triple pass between the cliff and the canyon opposite the two mountains. The existing Sandaoguan Great Wall is made of stone and hung upside down on a cliff. Just like the Youlong python winding down from the top of the cliff, straight into the bottom of the valley, and rushing up behind the mountain, it naturally forms the trend of "the Great Wall hanging upside down", which is amazing. If Wan Li Great Wall is one of the "Seven Wonders of the World" in ancient times, then "hanging the Great Wall upside down" is a must in the scenery of Wan Li Great Wall.

This section of the Great Wall is made of stone. The wall is 4.7 meters high, 2 meters wide and 468 meters long. The interior and exterior walls are built with white mortar, and the enemy platform is built with city bricks. In fact, this section of the Great Wall has no foundation, and there is no way to lay the foundation. It is built on bare stones, which are laid directly on the cliff and bite the stone surface of the cliff. Now hundreds of years have passed, and its lime-built surface is still there, without dislocation, and it is very well preserved.