Generally, caves are built on the hillside facing south, facing the sun, with the back to the mountain and facing the open area, which is very suitable for living and living. Generally, the caves in the First Hospital are built with 3 holes or 5 holes. The middle kiln is the main kiln, some of which are divided into front and back kilns, and some of which are 1-in and 3-in. From the outside, the four holes should be opened separately. When you walk inside, you can find that they have tunnel-type small doors and the top is semicircular, so that the space of the caves will increase. Cave walls are generally painted with lime, which looks dazzling, dry and bright. There is a pot and a stove on one side in the cave, and the stove is connected to one end of the kang. Because the flue of the stove fire passes through the bottom of the kang, it is very warm on the kang in winter. The three walls around the kang are generally pasted with some paper or collage paintings with patterns, which are called kang enclosures by people in northern Shaanxi. Kang enclosures are a kind of practical decoration, which can avoid direct contact and friction between the bedding on the kang and the rough wall and keep it clean. In order to beautify the living room, many people paint on the kang enclosure. This is a folk art with a long history in northern Shaanxi-Kang Wai painting. The windows of caves in northern Shaanxi are exquisite, which are divided into four parts: skylight, inclined window, kang window and doors and windows, all of which are decorated with paper-cuts. According to the pattern of windows, they decorate the window grilles beautifully and appropriately. The window grilles are stuck outside the window, and the colors are bright from the outside, but the interior is bright and comfortable, thus producing a unique formal beauty of light, color and tone. The panes are sparse, and sunlight can freely penetrate in.

The loess, which is as deep as 1211 meters, extremely difficult to penetrate water and highly upright, provides a good premise for the development of caves. At the same time, the natural conditions such as dry climate, cold winter and less wood have also created opportunities for the development and continuation of caves that are warm in winter and cool in summer, very economical and do not need wood. Due to the influence of natural environment, geomorphological features and local customs, caves have formed various forms. However, from the layout and structural form of the building, it can be divided into three forms: cliff-leaning, sinking and independent.

The caves in Yan 'an, northern Shaanxi, are mixed with cave-style flat-roofed houses. Cave dwelling is an organic combination of natural landscape and life landscape, which permeates people's love and attachment to the yellow land.

cliff cave

cliff cave has a backing type and a ditch type, and caves are often arranged in curved or broken lines, which has a harmonious and beautiful architectural artistic effect. When the height of the hillside allows, sometimes several terraced caves are arranged, similar to buildings.

sunken caves

sunken caves are underground caves, which are mainly distributed in the loess plateau-areas where there are no slopes or ditch walls to use. The practice of this cave dwelling is: first dig a square pit on the spot, and then go to the cave dwelling with four walls to form a quadrangle. On the flat ground, people can only see the treetops of the courtyard, but not the houses.

freestanding cave

freestanding cave is a kind of arched house covered with earth, including adobe arch cave and brick arch cave. This kind of cave does not need to rely on the mountain and cliff, and it can be independent without losing the advantages of the cave. It can be a single story or a building. If the upper floor is also a hoop kiln, it is called "kiln on kiln"; If the upper floor is a wooden house, it is called "kiln house".

The cave is fire-proof and noise-proof, warm in winter and cool in summer, which not only saves land, but also saves labor economically. It is indeed a perfect architectural form according to local conditions.

cave dwelling

cave dwelling this is a very old way of living, that is, digging transverse caves in the loess cliff area as living rooms. Because it has the advantages of simple construction, low cost, warm in winter and cool in summer, no damage to ecology, no occupation of fertile land, etc., although there are defects in lighting and ventilation, it is still a folk house in the loess area with little rain in the north. According to the construction mode, it can be divided into three types: cliff kiln, flat kiln and closed kiln. Cliff kiln is a voucher-top horizontal hole dug by natural soil wall, which can be single-hole or multi-hole, and can also be combined with ground houses to form a courtyard; Pingdi Kiln is also called Pit Yard, Dig Yard and Dark Zhuangzi. That is, deep pits are dug down on the flat ground to form artificial soil walls, and then caves are dug deep on the soil walls in all directions at the bottom of the pits, which can also be said to be a combination of vertical kiln and horizontal kiln. This type of cave dwelling is popular in Gongxian, Sanmenxia and Lingbao in Henan, Qingyang in Gansu and Pinglu in Shanxi. Gu Kiln is an independent cave dwelling built with brick or adobe on the flat ground by issuing vouchers. The vouchers are covered with soil to make flat-roofed houses for drying grain, which are mostly used in western Shanxi and northern Shaanxi. At present, cave dwellings in China are mainly concentrated in five areas, namely Jinzhong, western Henan, Longdong, northern Shaanxi and northwestern Hebei.