From the perspective of geomantic omen, the first principle of good geomantic omen is "surrounded by mountains and water on all sides". In other words, there are mountains to lean on, people to thrive, and water to surround and thrive in front.
Xuanwu Square in geomantic omen is the back of the house, which is the place with the back of the mountain. So the position of the backer is also called Xuanwu. If the position of the backer is not good, the chief official will be robbed by thieves. Because Xuanwu is the god of darkness, abnormal peach blossoms appear. Feng shui takes the front as the direction, in charge of wealth, and sits behind the mountain, in charge of people. Therefore, it is very important for the house to rely on the mountain. There is a real mountain behind the house. Beautiful mountains and rivers, Hua Mao vegetation, meaning that people living here are smart, delicate, beautiful and dignified.