Feixian Valley is the most magnificent and the steepest granite canyon in Sanqing Mountain. The canyon is about 2,500 meters long, with a V-shaped cross-section and a cut depth of more than 300 meters. Both sides are cliff faces that are impassable to humans, and only immortals can fly across, hence the name 'Feixian Valley.' It is a V-shaped canyon formed by the continuous erosion and incision of flowing water along the fractures and faults in the granite body.