Introduction to Bigan Tomb: It is the first recorded mound-style tomb in China. The tomb is round, like a heart, which means the heart of loyalty and the universe. There is a stone archway in front of the tomb, with stone carved dates on the left and right. Moon, with a heart-shaped stone carving in the middle. The implication is that Duke Bi Gan served the country loyally, and "the sun and the moon shine on the loyal heart."