From the perspective of the history of World Architecture, digging caves on the cliff as a temple began in ancient Egypt, became popular in ancient Persia, flourished in ancient India, and gradually affected Southeast Asia and China. India began to build Buddhist cave temples in the peacock king's Dynasty in the 3rd century BC, but at that time, as the mainstream of Buddhism, Mahayana Buddhism did not advocate idol worship. It usually represented the Buddha Sakyamuni Buddha with the pagoda. Therefore, there were no Buddha statues in the cave temples, and only Buddhist pagodas and other symbols representing the Buddha were enshrined. It was not until the rise of Mahayana Buddhism around the 1st century that idol worship was gradually accepted by the society, and Buddha statues became the protagonist in grotto temples.
Generally speaking, the Buddha statues in Grottoes can be divided into two types: the Buddha statues in murals and the stone Buddha statues, and the latter is more common. For example, the Buddha statues in Ajanta Grottoes in India and the standing Buddha with a height of more than 50 meters in Bamiyan Grottoes in Afghanistan. The most famous stone Buddha statues in ancient Chinese Grotto temples are the standing Buddha in Kizil Grottoes of Han Dynasty in Xinjiang, the Giant Buddha in tanyao grottoes of Northern Wei Dynasty in Yungang, and the Lushena Giant Buddha in Fengxian Temple of Tang Dynasty in Longmen Grottoes.
Longmen Grottoes is the longest continuous excavation, which took 24 years to complete. The grottoes are 1000 meters long from north to south, with more than 9700 Buddha statues and more than 1300 grottoes. The largest Buddha statue is 17.14 meters high and the smallest is only 2 cm high. Maijishan grottoes are named because the mountain looks like a pile of wheat. Most of the grottoes are excavated on the cliffs and cliffs 20 ~ 80 meters high, stacked layer by layer, as dense as a honeycomb. The caves are connected by plank roads, climbing up to the top of the mountain. The grottoes are characterized by clay Buddha statues. The size of the statues is similar to that of real people. They are known as the "Oriental statue Museum".
How were the Buddha statues in the grottoes built? First of all, the caves should be excavated. Professional cave hunters should carefully design the caves in advance according to the theme, shape and scale of the caves, and then carefully dig and construct on the mountains. The construction method is also exquisite. First dig the foundation to form the entrance and exit, then dig the doors and windows, and then excavate the grottoes. The excavation of grottoes should be carried out step by step from top to bottom. First, it is to avoid collapse and ensure construction safety; Second, to save labor and labor, it is convenient to send the sand from high to low. While digging caves, a special mud layer should be attached to the rock to draw murals.
The process of drawing murals is divided into three stages: drafting, coloring and drawing lines, while the shaping of Buddha statues needs to go through four stages: skeleton building, mud making, shaping and color application. Each process is completed by the cooperation of masons, painters, carpenters and sculptors. The ancient Chinese were very clever. They chose the tough and easy to bend red willow as the skeleton, so that they could show the details of the Buddha's dress belt when the wind was flowing. Through thousands of years of accumulation and summary, craftsmen have mastered the mural skills such as wet painting, and the murals drawn are exquisite, gorgeous and preserved for a long time. The final work is to decorate the eaves of the grottoes. The eaves are built on the top of the grottoes. It is a structure used to shelter from wind and rain. The completion of the eaves marks the completion of the construction of a grotto.