The “large ash trench” is a trench-shaped remains stretching from west to east in the north of the palace city of the Shang city in Yanshi and measuring 110m in length and 14m in width. Its excavation in 1996--1997 revealed a series of cultural layers with ideal stratigraphic evidence and plentiful objects. The discovery laid a solid foundation for the pcriodization of the remains in the Shang Yanshi city, providing a three-phase seven-subphase chronological frame for the early Shang vestiges in the city, with the first and second phases represented by the main deposits in the trench. Furthermore, it affords reliable material to the study of the Xia and Shang cultures and their chronology, enriching our knowledge of the early Shang culture represented by the Erligang remains, substantiating the contents between the Erligang period and the Erlitou culture, and advancing the research on the turn from the Xia to the Shang dynasties and the demarcation between their cultures.
In 1996, the Second Henan Archaeological Team, IA, CASS, excavated a tomb of the Eastern Zhou period in the northeast of the Shang city-site in Yanshi. The tomb is a rectangular earthen pit and features erected stakes around the pit. The wooden coffin contains a human skeleton in a flexed supine position. The funeral objects fall into two categories: pottery vessels and wooden ones. The former numbers six; and the latter, 13, poorer in condition. The tomb dates from the Spring-and-Autumn period and may be cultural remains of the "Shi clan." Its discovery has certain significance to studying the date and nature of the Shang city in Yanshi.