How to write if the tour guide introduces the cave?

Cave dwellings in China originated from cave dwellings and semi-cave dwellings in the Stone Age. Primitive ancestors found that the space of natural caves was suitable for living, with the functions of shelter from wind and rain, cold and summer, and defense. Loess has loose texture, well developed vertical joints, good integrity and moderate softness, and can be dug into caves with simple stone tools.

A common form of cave dwelling is cliff cave dwelling. People dig inward on the natural loess cliff and dig out horizontal holes, often several holes are connected together, and several rows can be formed from top to bottom, and each row is lined up by several holes to form a stepped hole group. People generally level the site in front of the cave into a dam, and build a retaining wall with masonry as an outdoor activity space. Therefore, the living environment of the whole village, whether indoors or outdoors, is closely connected with the natural mountains. On the one hand, it can save cultivated land and maintain soil and water; On the other hand, greening can be planted on the ditch wall to prevent the gully from expanding. From the perspective of environmental architecture, this is a perfect ecological building that does not destroy nature.

Cave dwellings can be divided into four types according to the different building materials used: earth kiln, stone kiln, brick kiln and combined kiln. The soil cave is the original state of the cave, that is, all buildings are built of soil, which makes full use of the advantages of thermal inertia and large thermal resistance coefficient of soil, so that the soil cave has good thermal insulation and constant temperature ability. Stone kilns are common in northern Shaanxi, because most of the mountains in that area are stone mountains. It is also a good choice to make a hole in the mountain wall or enclose the cave with stones, which can make full use of local materials, and the construction technology is simple, and the stability of the cave can be guaranteed with stones. Brick kiln is an arched cave made of brick and mortar, and its structure and advantages are similar to those of stone kiln.