Introduction to the trenches: The fortress has a power generation room, a warehouse, an ammunition depot, a health clinic, a dormitory, a dining room, a general room, and a command room. There are shooting holes at every intersection or turn to facilitate sniping during tunnel warfare. There are ditches for drainage on both sides of the bottom of the tunnel, so it is very dry inside. There are ventilation holes every 50 meters at the top of the tunnel, leading directly to the top of the mountain. The quality of the entire fortification is very good.