The Tet holiday in Vietnam is meant to be a joyous celebration to welcome the lunar new year and springtime with big family reunions and feasting.
However, it is also remembered for a very significant military engagement of the American-Vietnam War.
The Tet Offensive in 1968 was one of the largest campaigns, fought in a hundred towns and villages; it left thousands in the South Vietnam capital of Saigon dead and hundreds of homes destroyed.
It is also now recognised as a turning point when American public support for the Vietnam War started to collapse.
This series of surprise attacks by the Communist North Vietnamese forces happened during the Tet festivities and still shakes some residents of Saigon, or what is now known as Ho Chi Minh City.
Hannah Twiggs reports.