This is the remains of Sinanthropus pekinensis, who lived in the Middle Pleistocene, along with various objects, and remains of Homo sapiens sapiens dating as far back as 18,000-11,000 BC. The average brain volume of these people was 1,088 milliliter (the average for modern people is 1,400 ml). And it is estimated that their average height reached 156 cm for males and 150 cm for females. They chose to stay here for adequate water supplies and natural limestone caves, which provided an optimal survival environment.

Peking Man was among the first human beings to learn how to use fire, and could hunt large animals. Their average life expectancy was short; it is estimated that 68.2 percent of them died by the age of 14, and only 4.5 percent lived up to 50 years.