Introduction to Black Dragon Valley and Black Dragon Pool: The cliffs on both sides here are upright, with a wall height of 50 meters and a length of 20 meters. The width of the valley is only 1 to 3 meters. When you look up, you can only see a line of sky, which is the Black Dragon Valley. The water accumulates in the valley to form a pool, with a water depth of 4 to 5 meters. Because it is located in a deep valley and rarely receives sunlight, the color is deep and dark, hence the name Black Dragon Pool.