Ancient geomantic omen thought that Xuanwu, a house facing south, was located in the rear, which was suitable for tall houses, so it was suitable for arranging rooms such as halls to highlight its grandeur.
Xuanwu is one of the four heavenly spirits in China's ancient mythology, which originated from the worship of stars in ancient times. It is the northern Xuanwu seven lodges, of which 28 lodges are divided into four elephants according to the southeast and northwest. The image is a kind of spiritual thing composed of turtles and snakes based on gossip and five behaviors, symbolizing the old yin in the four elephants and the winter in the four seasons. Xuanwu, also called Xuanming, is a combination of tortoise and snake. It is the water god, living in Beihai, and the tortoise lives long. Xuan Ming has become an immortal symbol.