Introduction
The eastern part of the Sichuan Basin in south-west China borders the Daba Mountain and the Hanzhong Basin to the north, the Chengdu Plain to the west, and the middle reaches of the Yangzi River to the south-east. Owing to its unique geographical location, this area became a hub for communication between different regions and cultures as early as the Eastern Zhou (770–256 BC) and the Qin and Han dynasties (221 BC–AD 220). Yet the archaeological record for this region is under-represented. In recent years, several sites from the Warring States Period (c. fifth century BC–third century AD) and the Qin and Han dynasties have been discovered in eastern Sichuan Province. The Chengba site in Tuxi Town, Quxian County, sits south of the Daba Mountain, and the Micang Pass provides a passage through this mountain leading to the Central Plains (Wang Reference Zijin2013). The site is on the east bank of the Qujiang River, which flows south into the Jialing River and eventually into the Yangzi River (Figure 1). The geographical positioning facilitated exchange between this area and the middle reaches of the Yangzi River. Activity at the site, including house foundations, city site and evidence for smelting, is some of the first archaeology from the Warring States Period dated to the Han and Jin dynasties discovered in eastern Sichuan (Liu et al. Reference Huashi, Wenfeng and Shenxin2005; Chen & Zhou Reference Weidong and Kehua2006; Liu Reference Huashi2006; Zheng et al. Reference Luhong, Weidong, Kehua, Chongliang and Lianghong2019). Excavated artefacts include bronze objects, inscribed eave-end tiles, bamboo slips and smelting-related products (Figure 2).
Figure 1. Location of the Chengba site (base map source: Geospatial Data Cloud, figure by authors).
Figure 2. Representative artefacts excavated from the site: a) bronze musical instrument; b) eave-end tile inscribed with ‘Dangqu’ characters; c) U-shaped iron implement cap; d–f) bamboo slips (figure by authors).
Cong City and Dangqu City
A city site of the Han Dynasty with a total area of approximately 50 000m2 has been found at Chengba. The discovery includes a gated city wall, of 725m circumference with a surrounding moat, as well as streets and building foundations. Large numbers of eave-end tiles inscribed with ‘Dangqu’ characters have been excavated at the site (Zheng et al. Reference Luhong, Weidong, Kehua, Chongliang and Lianghong2019). Based on the artefacts unearthed, it is suggested that the city walls were initially built during the early Western Han Dynasty (202–141 BC) and underwent multiple repairs thereafter (Chen & Zhou Reference Weidong and Kehua2021). At present, the Han Dynasty city sites discovered in Sichuan Province are mainly distributed in the Chengdu Plain, and the city site at Chengba is the first Han Dynasty city discovered in eastern Sichuan Province. Based on archaeological evidence and related research, the Chengba site was an early, large and long-lasting city (Chen Reference Weidong2020). A cemetery area, pottery-making area and dock area are identified around the city site (Figure 3). The dock area is on the bank of the Qujiang River in the north-west of the city site. Considering its geographical placement and the contents of the bamboo slips discovered there, it is proposed that this place was a land and water gateway for inspecting personnel and ships, controlling the flow of resources and the trade of goods. If so, this is the only water gateway from the Han Dynasty discovered in China to date (Zheng et al. Reference Luhong, Weidong, Kehua, Chongliang and Lianghong2019).
Figure 3. Schematic diagram showing different social functional areas around Chengba (figure by authors).
Based on the bronze artefacts of the Warring States Period excavated at Chengba and comparison with historical documents, Chen and Zhou (Reference Weidong and Kehua2021) suggest that the Chengba site corresponds to the ancient ‘Cong City’ from the Warring States Period to the early Western Han Dynasty. On the other hand, multiple historical records indicate that the ‘Dangqu County’ was established during the Han Dynasty, being part of Ba Commandery, and details of its probable location correspond with the location of the Chengba site. Combining the historical records with the large number of excavated ‘Dangqu’ eave-end tiles, the Chengba site is very likely the ancient Dangqu City of the Western Han Dynasty. The Chengba site is in a complex hilly region where land transportation, even today, is difficult, but it was clearly of great political and geopolitical significance for the city to be established there at that time. With the help of river transportation and a passage through the Daba Mountain, the Chengba site was an important hub of communication between the Central Plains and the middle reaches of the Yangzi River from the Warring States Period to the Qin and Han dynasties.
Excavated objects
During the Waring States Period, present-day Quxian County was situated within the likely boundaries of Ba state. The bronze sacrificial vessels and weapons excavated at Chengba suggest that this was an important area for social activity in the Ba state as early as the late Warring States Period and will contribute substantially to future studies of social change in the Ba state. The bamboo slips and the iron-smelting waste from the Han Dynasty are the first examples found from this period in eastern Sichuan. The contents of the bamboo slips cover various topics including judicature, finance and education (calligraphy, literature and arithmetic). Few bamboo slips about registered residence have been unearthed in China, and the discovery at Chengba provides valuable insights into the household registration system of the Western Han Dynasty (Ling Reference Wenchao2020). The items also provide a window into education systems, local administrative institutions and daily life of residents during the Han Dynasty.
More than 20 000 fragments of slag, furnace lining and tuyere (the nozzle through which air is forced into the furnace) were discovered at the Chengba site. Based on the large amounts of excavated slag and the span of radiocarbon dates, these artefacts are an important demonstration of continuous smelting activities at the site between the late Western Han Dynasty and the middle of the Eastern Han Dynasty (Figure 4). The abundance of iron-smelting-related artefacts provides important archaeological evidence for studying iron production and circulation in eastern Sichuan Province during the Han Dynasty.
Figure 4. Probability distributions for radiocarbon dates relating to iron-smelting activities (figure by authors).
Conclusions and future research
The distribution of different functional areas at the Chengba site has been clarified through systematic archaeological investigation. Its prime geographical location and abundant natural resources indicate that the site was clearly an important urban settlement from the late Warring States Period to the Qin and Han dynasties (c. fourth century BC to third century AD). The different social functional areas distributed within and around the city site provide valuable information for studying population size, living environments, urban functions and local administrative systems of a Han Dynasty county. Future work will focus on identifying more functional areas and further revealing the internal layouts of the key functional areas, thus enhancing our understanding of the relationships between each area. Systematic research will also be undertaken to delineate the internal chronology and development of the site.
Acknowledgements
Thanks to the Chengba site archaeologists of the Sichuan Provincial Institute of Cultural Relics and Archaeology.
Funding statement
This work was funded by the National Natural Science Fund of China (T2350410495), the Ministry of Science and Technology of the People's Republic of China (2022FY101505) and Sichuan University (SKSYL2023-05 & 2035xd-02).
