Operation Coburg (24 January − 1 March 1968) was an Australian and New Zealand military action during the Vietnam War.
The operation saw heavy fighting between the 1st Australian Task Force (1 ATF) and North Vietnamese Army and Viet Cong forces during the wider fighting around Long Binh and Bien Hoa.
American and South Vietnamese intelligence reports had indicated that an imminent communist offensive during the Tet New Year festival was likely, and in response the Australians and New Zealanders were deployed away from their base in Phuoc Tuy Province to bolster American and South Vietnamese forces defending the Long Binh–Bien Hoa complex north-east of Saigon.
1 ATF deliberately established fire support bases astride the communist lines of communication in the vicinity of the village of Trang Bom, expecting that they would attempt to destroy them.
The Australians subsequently clashed with the Viet Cong during early patrols in Area of operations (AO) Columbus, while later Fire Support Base (FSB) Andersen was repeatedly subjected to major ground assaults.
Although the operation was mounted too late to prevent the attacks on Saigon, the Australians and New Zealanders successfully disrupted the communist lines of communication, limiting their freedom of manoeuvre to attack the Long Binh–Bien Hoa complex, while they were also able to successfully interdict their withdrawal, causing heavy casualties.
The operation was also significant as it was the first deployment of 1 ATF outside its Tactical Area of Responsibility (TAOR) in Phuoc Tuy, and in this it set a precedent for later operations outside the province.
Meanwhile, the remaining Australian forces in Phuoc Tuy Province also successfully repelled repeated Viet Cong attacks against Ba Ria and Long Dien, as part of the Tet Offensive that had engulfed population centres across South Vietnam.