According to a joint statement issued on Wednesday, China and Vietnam finally drew a line across their differences over their land borders, which were at the root cause of the war between the two communist neighbours.
China and Vietnam have "finalised the demarcation and placement of markers along the entire land border between Vietnam and China," following an accord by senior officials in both countries, the statement said.
On February 17, 1979, at dawn, after several months of escalating tension, 200,000 Chinese soldiers launched a major offensive into Vietnamese territory.
What became known as the third Indochinese war took place against a background of deep ideological rivalries within the communist bloc between Beijing and Moscow, the Soviet Union being Vietnam's privileged ally in Asia.
The operation, qualified by Beijing as a "counter-attack in self-defence", had been preceded by heavy bombings by artillery along most of the localities situated along the disputed 1,400 kilometres (870 miles) of frontier between the two countries.
During the 1979 war Chinese troops penetrated several dozen kilometres inside Vietnamese territory and took control of several towns — notably Lang Son, Cao Bang, Lao Cai and Mong Cai — before withdrawing a month later on March 16.
According to tolls published by Beijing, this brief war left 50,000 dead or injured on the Vietnamese side against 20,000 on the Chinese side. Vietnam contests the figures.
From the beginning of the operation, the Chinese authorities stressed that the "counter-attack" would be of limited scope and that China had no territorial claim on Vietnamese territory.
Beijing's objective was to punish Hanoi for continued armed provocations on Chinese territory and to teach a lesson to Vietnam, whose troops had six weeks earlier on January 7 overthrown the Khmer Rouge regime of Pol Pot, who had been in power in Cambodia since 1975 and was backed by Beijing.
The Chinese offensive was also launched as the Vietnamese prime minister at that time, Pham Van Dong, was for the first time officially received in Phnom Penh by Heng Samrin, the head of the new regime put in place in Cambodia by the Vietnamese army.