What's the difference between Shengji Cave in Sichuan and an ancient tomb?

The differences between Shengji Cave and ancient tombs in Sichuan are as follows:

1, Shengji Cave in Sichuan, the internal structure of the foundation is brick or stone arch. The purpose is to dry the interior and slow down the decay rate of coffins and corpses.

2. Shengji Cave in Sichuan. In many cases, the construction of Shengji tomb was completed before the death of the deceased, and it was directly carried into the tomb after the death of the tomb owner.

3. Tomb, where the coffin is placed in the tomb, and whether there is space for the arch structure at the top of the tomb, especially if it is partially or completely underground.