More than 200 primitive stone weapons about the size of basketballs were on display Monday in Luanping City, north China's Hebei Province.
The weapons were believed to be primitive forms of grenades, said Wu Yuehua, an official with the city's cultural heritage bureau.
She said they were collected from the Jinshanling section of the Great Wall by villagers living near the defence work.
"At least half of them were collected by villager Bai Chunxiang and his family," she said.
Bai, who followed his father and grandfather to collect relics from the Wall, has donated his collection to the cultural heritage bureau.
The stone grenades weighed from 10 to 50 kg each.
Wu said the weapons were at least 500 years old.