In order to implement the Resolution No. 15 of the Party’s Central Committee (the second session) about the twinning between provinces and cities in the North and provinces and cities in the South for the purpose of creating collective power of the entire nation to carry out the resistance war against the American imperialist, on March 12^th, 1960, a twinning ceremony between Thanh Hóa Province and Quảng Nam Province took place in Thanh Hóa Town (which is now Thanh Hóa City).

The delegation of was led by Mr. Trần Đình Tri, Secretary General of the first National Assembly of the Democratic Republic of Vietnam, who was accompanied by representatives of the Central Unification Board. The delegation of included representatives of the Thanh Hóa Provincial Committee of the Party, Thanh Hóa Administrative Committee, and Thanh Hóa Provincial Fatherland Front. The ceremony was carried out formally, which was then followed up by twinning ceremony between the districts, for example Tĩnh Gia and Đại Lộc, Hoằng Hóa and Điện Bàn, Đông Sơn and Thăng Bình, Quảng Xương and Hòa Vang, Thọ Xuân and Quế Sơn, Triệu Sơn and Tam Kỳ, and Nông Cống and Duy Xuyên...