The Potala Palace, located on the Red Mountain in Lhasa, is a world cultural heritage and a masterpiece of Tibetan architecture. It embodies the wisdom of the Tibetan people and is still a miracle in the history of world architecture, known as the "Pearl on the Roof of the World". Entering the Potala Palace from the main entrance, walking up the steps, you can see the smooth top of the wall and the roof. Walking into the palace, the smooth ground also attracted the attention of many people. These are the use of a unique craftsmanship in Tibetan architecture - "Daga".

When was Agga used as a building material in Tibet? Why do we say that without this traditional skill that has been passed down for thousands of years, there would be no Potala Palace that attracts the attention of the world? According to historical records, from the construction of Yongbulakang, the first king of Tubo, Nie Chi Zanpu, to the construction of religious buildings such as Jokhang Temple, Ramoche Temple, and Potala Palace by Songtsen Gampo 1,300 years ago, Aga soil was widely used. . In the Tubo period, Aga soil was widely used as a building material, and the use of Aga soil has a history of more than 1,000 years. The famous Potala Palace uses the most Aga soil, and many grounds in the palace are made of Aga soil.

"Guests from afar, please look at me, my singing is more beautiful. The ground of Aga land is as flat as a mirror, and the singer is showing affection. The tiger-like boy is approaching me..." Harmony, accompanied by the sound of Aga's beating came from the Potala Palace under construction. Before the emergence of modern building materials such as cement and concrete, bricks, tiles and lime were used as the main masonry materials in ancient buildings in the Mainland. Due to the oxygen-deficient natural environment of the Tibetan plateau, it is extremely difficult to burn bricks and tiles, and it is difficult to find building limes that meet the standards due to the unique geographical environment of Tibet. It is inevitable and unique in the ancient national architectural craftsmanship. The surface of Aga is smooth and bright, and the house rammed with Aga can be more sturdy, insulated and waterproof. If the wooden beams on the roof break, the roof will remain stable with the help of Aga's stickiness and will not collapse.

"Aga" is Tibetan and means "white matter". Aga is a microcrystalline limestone with both soil and stone facies, and it is produced in some half-earth and half-stone mountain bales in Tibet, and the storage site is in the 1-2 meters thick stratum on the upper part of the mountain. Qushui, Linzhou, Dazi and other counties near Lhasa, and Zhanang County in Shannan have storage. The long-term testing of materials from the origin by construction experts shows that the proportion of Aga materials (silicon and calcium) produced in Zhanang County is relatively reasonable, and the building surface layer after construction with this material is also relatively strong and beautiful. Although the journey is long, some important buildings such as the Potala Palace and Jokhang Temple in the urban area of Lhasa all use the Aga soil here.

The process of "playing Aga" is very complicated. First, the mined rough "Aga soil" is spread on the pebbles and the compacted soil layer, about 10 cm thick, and then rammed with "silk duo" after being sprayed with water. "Bo Duo" is a special Tibetan tool for "playing aga". The top is a wooden stick and the bottom is a bluestone with a hole in the middle. While ramming, lay a layer of "Aga soil" that is thinner than one layer, and keep pouring water until the surface of the slurry is smooth and clean. Then, smooth the ground with pebbles, and then wipe the ground two or three times with the juice soaked in elm bark. Finally, it is coated with highland barley oil and honey, which are common in Tibet, to increase its water resistance. After a thousand hammers, Aga is very strong. People can clearly see that Aga clods of different sizes are inlaid on the ground, mixed with ochre red resin, bright and smooth, and feel like natural marble.

The production of Aga ground is time-consuming and labor-intensive. Even the configuration of one craftsman per square meter takes more than 20 days to complete. The larger the area, the more people participating, ranging from dozens to hundreds. Playing Aga is very skillful and requires certain strength. Sometimes the force should be uniform to ensure that the ground is level; During the 7-8 day group making process, it is necessary to cooperate with each other tacitly. If one person cannot keep up with the rhythm, the ground may be uneven. The craftsmen who beat Aga are usually young and strong, with similar height and weight, and they beat with men and women. The woman is in charge of the beginning, filling and beating four different sizes of Aga clods layer by layer, including large, medium, small, and powder, until they are leveled;

The process of making the roof or the ground with Aga soil is called Da Aga. In "Da Aga", men and women, old and young, form a line, walking around while beating, singing and dancing. Dynamic picture with strong sense of rhythm. "Those who can't sing, can't learn to play Aga." There is such a saying in the Aga industry. One square meter of Aga requires at least 20 days of construction to complete. If you work hard, few people will be able to persevere. The Tibetan ancestors who are full of wisdom have introduced the Aga, which is often sung in daily production and life, into the production process of Aga. When the "Bo Duo" landed on the wet roof neatly and uniformly, it made a "bang, bang, bang" sound, like a subwoofer accompanying the singing, thick and deep, dancing with a tap dance-like rhythm and melody . The feet of the girls and the boys kept stomping on the ground, in keeping with the rhythm of "Bo Duo", sometimes fast, slow, light and heavy, with graceful figures and light steps, "Bo Duo" was sometimes held on the left and sometimes on the right. , so stretched, so harmonious, evenly curved, clever and clumsy. The hard work is also done unknowingly.

The formation of Agage can be traced back to the early Tubo Dynasty more than 1,300 years ago. Songtsen Gampo and Princess Wencheng and Princess Chizun built large-scale temple buildings such as Jokhang Temple and Ramoche Temple, and recruited many craftsmen and migrant workers from the U-Tibet area, who brought folk songs and dances from various places. During the construction of the temple, they sang while doing the work, forming the first batch of Aga songs. In the period of Pamuzhuba, the second architectural climax was set off. Drepung Monastery was built on the outskirts of Lhasa, Sera Monastery was built in the northern suburbs, and Gandan Monastery was built in the eastern suburbs. "Soil production process" has both been shortlisted in the autonomous region-level intangible cultural heritage list.