The mass grave at Meiyukou south gully is a well-preserved and large site witnessing the atrocity, featuring two caves filled with layered skeletal remains. The upper pit is about 5 to 6 meters wide and more than 40 meters deep. The lower pit is about 3 to 4 meters wide and over 70 meters deep.

In 1966, researchers began the process of clearing and identifying the remains in the two pits at Meiyukou. They conducted detailed examinations of the conditions and ages of the remains with about 200 sets of bones excavated and cleaned. The average age of the deceased miners was 32.8 years old, with the oldest being 56 and the youngest 16, and there were no females in the pit.

During the clearing process, the facial expressions of some of the remains were clearly visible. Some of the deceased miners appeared to be struggling to crawl toward the cave entrance, some were touching their wounds, some seemed to be calling for help with their mouths open, and others showed expressions of fear, pain and despair.

"Seeing the actual remains at the heritage site is profoundly shocking. It must be seen," Guo says, adding that they need to deepen the research and harness new media to amplify this history to visitors from home and abroad.

He emphasizes the museum's dual purpose: mourning victims while championing peace through intergenerational education, particularly because this year marks the 80th anniversary of the victory in the Chinese People's War of Resistance Against Japanese Aggression and the World Anti-Fascist War.

The Japanese invaders' ruthless plundering of the coal resources and their brutal rule and persecution of the miners provoked widespread anger and resistance among the workers, who launched an unyielding struggle against the occupiers. They sabotaged tools and equipment, caused production stoppages, engaged in passive resistance, went on strikes, conducted secret armed struggles, and punished collaborators. The persistent resistance of the miners repeatedly thwarted the Japanese invaders' plundering plans.