An immense record of early humans
The Nihewan Basin is not a single location but a vast, 9,000-square-kilometer geological formation that holds one of the densest concentrations of Early Pleistocene Paleolithic sites anywhere outside of Africa. For over a million years, this area was a large lake, creating layers of sediment that preserved a long and nearly continuous record of early hominin activity. More than 100 Paleolithic sites have been identified here, with the oldest, Majuangou, containing stone artifacts dated to approximately 1.66 million years ago. Another significant site, Xiaochangliang, dates to around 1.36 million years ago.
The tools found at these early sites are primarily simple, Oldowan-like (or Mode 1) implements. Hominins here skillfully selected chert, volcanic, and siliceous dolomite rocks to create flakes, cores, and scrapers. These toolkits show a practical approach to butchering animals and processing other materials. No hominin fossils have been found in direct association with these oldest tools. The evidence is entirely behavioral, left behind in the form of thousands of stone artifacts. Later sites in the basin, such as Cenjiawan, show technological advancements. By 1.1 million years ago, hominins at Cenjiawan were using prepared core techniques, a Mode 2 technology that demonstrates more complex planning to produce standardized, slender flakes for specific tasks.
A Pleistocene lakeshore ecosystem
The layers of sediment in the Nihewan Basin also preserved a record of the ancient environment. Paleoenvironmental data from pollen and sediment analysis show that early hominins lived on the margins of the Nihewan paleo-lake, in a temperate landscape of open grassland and wooded areas. The animal fossils found alongside the stone tools confirm this, pointing to a varied fauna.
The remains include extinct species of elephant (Mammuthus), deer (Eucladoceros), horse (Equus), and rhinoceros. At the Majuangou site, direct evidence of butchery was found where a stone scraper was in contact with an animal rib, showing impact marks from processing a carcass. This find provides a clear link between the stone tools and their use in acquiring food. The sheer abundance of animal bones and artifacts across many layers shows that hominins—likely Homo erectus—occupied this basin persistently, adapting to the lakeside environment over hundreds of thousands of years.