The four gods on the exterior wall of Xidan Civil Aviation Business Building

In ancient times, the ancients divided the sky into the East, West, South, and South, and were named after Qinglong (Canglong), Baihu, Suzaku, and Xuanwu (a turtle-shaped god). In fact, the sky is divided into four parts, formed by connecting the seven main satellites in each part and named after its shape.

Qinglong is one of the four elephants in Chinese traditional culture. According to the Five Elements Theory, it is the mythological animal that represents the East. Its orientation is east and left, and it represents the spring; the position of the white tiger is west and right, it represents the autumn; the position of the Suzaku is South, before, on behalf of the summer; basaltic position is the north, after the winter.