From Chengtou Mountain to Chicken City - how many unsolved mysteries are there in the Liyang Plain?

A few days ago, the ruins of Jiming City in Lixian County, Hunan Province, were selected as the top ten new archaeological discoveries in the country in 2021. In the same Liyang Plain, only 13 kilometers away from the ruins of Jiming City, the ruins of Chengtou Mountain were twice selected as the top ten new archaeological discoveries in China in 1992 and 1997. Liyang Plain is one of the most densely populated areas of prehistoric sites in mainland China, with a total area of about 700 square kilometers, and more than 200 Paleolithic sites have been discovered, more than 30 remnants of the transition period from Paleolithic to Neolithic, and more than 500 Neolithic sites.

At present, China has found the earliest and most complete wooden building foundation, the earliest rice field, the earliest city pool, the earliest sacrifice platform... There are still too many unsolved mysteries in the land of Liyang Plain waiting to be explored.

Wooden architecture refreshes the history of Chinese architecture

The 4700-year-old complete wooden building foundation found at the site of Jimingcheng is the earliest and most complete wooden building foundation found by archaeology, and this wooden building foundation is numbered F63, which is a prehistoric "mansion" excavated after two years by the Hunan Provincial Institute of Cultural Relics and Archaeology and the College of Archaeology of Sichuan University. It is generally sitting north facing south, for a regular rectangle, by the main building and the outer corridor composition, the main building length of 42 meters, width of 10 meters, 5 bays 7 rooms, an area of 420 square meters, plus corridors, the total area of up to 630 square meters, estimated, about 4700 years ago, and is likely to be two or more high-grade buildings, its scale and volume, the preservation of complete, for the first time in a hundred years of Chinese archaeology, refreshed the history of continental wooden architecture.

"The ancestors not only had a sense of site selection, but also a sense of material selection." Guo Weimin, chairman of the Hunan Archaeological Society and project leader, introduced that these woods are not ordinary wood, but high-grade building materials that are not easy to deform and crack - nan wood and camphor, and even a lot of gold silk nan wood.

There are other reasons that truly amaze the archaeological community and establish F63's place in the history of timber architecture.

In China, the most "old" wooden house is a dry-column building found at the Hemudu site in Zhejiang Province, more than 1,000 years before F63. But the F63 of Chicken City is very different from the dry-column building. Early dry-column buildings had no foundation, and wooden columns were inserted directly into the mud, touching soft mud and often sinking. In order to ensure the long-term stability of the house, F63 began to have the concept of building a foundation.

On the site, in a series of long, wide and deep base grooves, there is an impartial cushion of nearly half a meter wide, 8 meters long, 0.1 meters thick complete wooden planks, the wooden board is chiseled with large holes, and the half-meter thick wooden pillars are tightly embedded in the holes, and the perfect and stable foundation is formed. Based on the arrangement of the wooden pillars, as well as the tenon and tenon structural fragments found at the scene and the ropes used to lift the wooden planks, Zhang Tao, a researcher at the Hunan Provincial Institute of Cultural Relics and Archaeology, speculated that the house probably combined the construction method of piercing bucket and lifting beam. This architectural craft is already comparable to modern architectural craftsmanship.

After the foundation of this wooden building was born, the archaeological community gave it a high historical positioning and value positioning: the wooden building represented by F63 provides important information for understanding the prehistoric architectural form and technology of the Yangtze River Basin, and its discovery fills the gap in the history of Chinese prehistoric architecture and enriches the content of China's civil architecture history.

The old city wall corrects the history of Chinese city building

Located 13 kilometers away from The Chicken City, there is the ruins of Chengtou Mountain. Its existence predates the ruins of Chicken City by more than 1,000 years.

The period of decline of Chengtou Mountain was the period of the rise of the chicken city. Is there a connection between the two cities?

The ruins of Jiming City and the ruins of Chengtou Mountain are listed as "cities", one of the reasons is that they all have artificial rammed walls. Part of the walls of The Chicken City were damaged incompletely due to late destruction. A section of the ancient city wall on Chengtou Mountain has been fortunately preserved.

In the Chengtoushan Site Museum, an exhibition hall displays the broken walls of the city wall, and the rammed layers of different colors are clearly visible in the soil section, and as early as the winter of 1991, archaeologists conducted an anatomical analysis of the southwest city wall, and divided the soil layer into twelve layers from top to bottom in chronological order. Each layer of soil contains the code of time, and archaeologists trace the origins layer by layer to explore the oldest roots of Chengtou Mountain, and finally determine that the city wall was built more than 6300 years ago. In those days, people took soil in the trenches and built the city out of it. The height of the city wall is only 2 meters, but because there is a height difference of 1.5 meters from the base of the wall to the opening of the trench, there is a ring trench under it that is 2.5 meters deep, and the combination of the three plays an effective defensive role.

Over the past thousands of years, the city wall has been added many times, gradually forming a specification of more than 1,000 meters long, more than 30 meters wide and 5 meters high, with four gates in the east, south, west and north, and a moat of nearly 40 meters wide excavated.

There is a perfect urban planning in the ancient city, and the residential area, pottery area, sacrifice area and tomb area are strictly separated. The layout of the living quarters is also quite exquisite, and the living rooms are connected to the council chamber and separated by wooden bone mud walls, and their upward orientation is also different. The city has wide urban avenues with drainage facilities, dense and overlapping public tombs, and smoky pottery kiln workshops. Today, at the site of Chengtou Mountain, you can still see the remains of the city's facilities.

The urban fireworks of Chengtou Mountain have existed for more than 2,000 years, through several historical periods of Daxi culture, Qujialing culture and Shijiahe culture, until the middle of the Shijiahe culture (about 4,000 years ago), when the ancient city was abandoned.

Ancient rice paddies rewrite the history of farming in China

In this vast field, archaeologists found footprints and plough marks left by ancestors when they farmed under the soil layer more than one meter deep, which were clear and eye-catching.

This discovery made Feng Jianping, deputy research librarian of the Lixian Cultural Relics Protection Affairs Center and engaged in archaeological work for more than 30 years, excited: "These rice fields that have been cultivated, I believe there will definitely be such historical traces, recording the agricultural state thousands of years ago." ”

The ancient rice fields of JimingCheng are distributed between the double ring moat and the triple ring moat of the ruins of Jiming City, and the rice field is also divided into parallel water channels, and connected by water systems, forming a complete irrigation system. To this day, this irrigation system still serves rice cultivation.

At the same time, archaeologists also found a large number of piled chaff on the west side of the large wooden building in Jiling City, and the uncovered part alone reached an area of 80 square meters and a thickness of 15 centimeters. It has been estimated that 22 tons of rice produce these grain brans, and about 14 tons of rice after shelling, which can be eaten by 1,000 adults for more than 40 days, which is only a small part of the excavation, and the actual area is much larger.

The discovery of grain bran, plough marks, footprints, and ancient rice fields shows that more than 4,000 years ago, the rice farming in Jimingcheng was already highly developed, and the level of rice cultivation was already quite superb, and it could even support a large number of people.

At the base of the city wall at the Chengtoushan site, archaeologists have found ancient rice fields dating back about 6,500 years, with regular mounds, gray mud, and clearly visible snails, rice leaves, stems, whiskers, and rice. On the native soil west of the rice field, there are also artificially excavated ponds, ditches and other preliminary supporting irrigation facilities. This ancient rice field has been identified by archaeologists as the earliest surviving rice field in the world.

The ancient rice fields of Chengtou Mountain can be called the source of rice cultivation. The earliest rice grains found in the Liyang Plain can be traced back more than 9,000 years.

In 1988, the Pengtou Mountain site, which is 11 kilometers away from the ruins of Jiming City and 2 kilometers away from the chengtou mountain site, found the world's earliest traces of rice farming - rice husks and grains , about 9,000 years ago. These rice husks and grains are largely mixed in pottery chips to raise the firing temperature of pottery products, and there are obvious stalks and rice leaf imprints in the pottery pieces. This discovery laid the foundation for establishing the historical position of the middle reaches of the Yangtze River in the origin and development of rice agriculture in China and even in the world.

In addition, in 1996, at the site of Bashiyuan, which is 6 kilometers away from the ruins of Jimingcheng and 18 kilometers from the ruins of Chengtou Mountain, archaeologists excavated nearly 10,000 grains of carbonized rice that are about 8,000 years old. Their discovery provides important information for scientifically and completely understanding the group characteristics and status of "ancient cultivated rice" in the process of plant evolution, and understanding the true face and development status of primitive agriculture. The remains of rice cultivation found in the eighty dam sites not only show the original form of ancient rice to the world, but also indicate that the middle reaches of the Yangtze River are the most developed primitive rice farming areas in the world.

All kinds of evidence proves that the ancestors not only completed the transformation from hunter-gatherer to agricultural civilization in the Liyang Plain, but also successfully completed the secondary transformation from agricultural civilization to urban civilization.

(Reporter Yu Aihua of this newspaper, correspondent of this newspaper, Xu Hongyu, Dai Yanhong)

(Guangming Daily)