Introduction to Shimen Pass: Shimen Pass is a natural gap formed by years of flood erosion at the stratigraphic faults of the Huaying Mountains. The Shimen is open to the sky and is extremely dangerous. It is the only way to enter the Huaying Mountain Grand Canyon. It is also a majestic pass that "one man can pass, and no one can enter". Legend has it that when the Qin State destroyed Ba, Prince Ba ordered his soldiers to defend this pass so that the Qin army could not advance. It was precisely because of this that the Ba people lived in caves in the mountains, leaving a remnant of the Ba people and the Ba culture passed down to this day.