The cannons were discovered while Hiep Thanh company was dredging theNavy’s docks in the central coastal city of Quy Nhon .
The museum’s Director Dinh Ba Hoa said that the four cannons are madeof bronze and cast iron and weigh from between 500kg to more than onetonne each. They were last used by the Tay Son insurrection (1771-1802)in Binh Dinh./.