The first primitive Chinese sunken courtyard dwelling dates back to around 2000 B.C. in the provinces of Shaanxi and Shanxi, China by most of the Jiaxian County. It is been known that these underground housings precedes the houses built above ground. Even after 4 millenniums, there is still around an estimated 30-40 million Chinese who lives in these shelters today and are confined to the region along the Yellow River in Northern China. The yellow earth, also known as "loess soil" of this region is structurally uniform and free of stone, plants, and trees. This presents an ideal condition for easy digging and stable form of foundation. The notable sunken courtyards are a large square or rectangular pit dug in about 10 meters deep with arched cave dwelling units dug around the perimeter.The scarcity of rain had made the provinces of Shaanxi and areas of northwest China extremely arid and dry. Despite of its supposed inhabitability, people did live there generations amongst generations through thousands of years. Considering that an area short of rain, timber, stone and fuel utilized in baking bricks, with extreme cold winds and sandstorms, it is of no surprise the Chinese chose to dig a sunken courtyard to be their shelter and home. The cave rooms that branches off from the courtyard insulated heat during long, cold winters and also remain fairly cool in the summer. One of the difficulties that they dealt with was when it did rain, there was a heavy downpour. The courtyards would accumulate the rain and a potential flood might occur. To solve this problem they built a drainage system that left through the exterior of the structure.Cave-type dwellings such as the sunken courtyards make ideal settings for the traditional extended Chinese family structure. The traditional patriarchal family, with ties and interrelationships, is strengthened by the proximity of the cave dwelling environment. The sunken courtyard is the main complex of the structure where daily conversations and gatherings occur, much like a very small town. The courtyard branches off into arched doors where different families of the extended family reside in. The distinct designs of the dwellings reflect a tradition of communal living, limited interaction with outsiders, and enclosure or protection of family members. It is a tradition that fosters a sense of unity.The interior decorations varied differently between other courtyard dwellings. Some left bare earth on the wall and floor while others lay treated bricks or tiles instead. It is mainly subjected to family's affordability. Despite of financial capabilities, even the poorest family would paste posters as well as other decorations on the wall during spring festival season. No roof mound of these courtyard dwellings is seen growing crops for fear of water leakage. As an alternative, a frequently used measure is to make the mound a flat concrete or brick surface for preventing the top of dwellings from collapse along with functioning as a sun-drying platform. Brick or stone are often added to the door arch of cave for additional strengthening against rain scour. In most courtyards various trees such as apple tree, pear tree, poplar and other Chinese "scholartree".It seems that tribes such as the Jiaxian County built these courtyards simply by digging ten meters deep into the ground, working from the interior of the structure toward the exterior. Once the main complex of the courtyard is done, they would start focusing on the drainage system to lead excess water out of the exterior wall without eroding it. Then each room of the dwelling and the entrance to the courtyard from the outside will be dug out where the arched doors or staircase would be formed.Although the concept may be simplistic, the work is very strenuous. The rough arid ground of the earth seems almost impenetrable and it takes a lot of time to break through. Despite what seems to be a rough and inhabitable environment, many Chinese still reside in these homes today living the life exactly similar to the way their ancestors did 4 millenniums ago.
