Introduction to the main tomb: The main tomb is a wooden coffin tomb in a rock pit with a sloping tomb passage, with a total length of 37 meters, a width of nearly 16 meters, and a depth of about 10 meters. It is divided into two layers of inner and outer coffin chambers. The outer coffin is surrounded by more than 400 thick and short timbers layer by layer. It is huge in scale, rigorous in structure and magnificent in momentum, just like an "underground palace" in the Han Dynasty. The tomb is composed of "Zigong" (coffin), "Bianfang" (coffin room), "Huangchangticuo" (short wooden canopy), and "Outer Tibetan Coffin" (corridor).