Major religious festivals in Vietnam have lunar dates; check against any Vietnamese calendar for the Gregorian dates. If you know when Tet kicks off, simply count from there. Special prayers are held at Vietnamese and Chinese pagodas when the moon is full or a thin sliver. Many Buddhists eat only vegetarian food on these days, which, according to the Chinese lunar calendar, fall on the 14th and 15th days of the month and from the last day of the month to the first day of the next month. Tet (Tet Nguyen Dan) The Big One! The Vietnamese Lunar New Year is Christmas, Hew Year and birthdays alt rolled into one. Lasting from the first to seventh days of the first moon, the Tet Festival falls in late January or early February for more on Tet. Holiday of the Dead (Thanh Minh) It's time to honour the ancestors with a visit to graves of deceased relatives. Fifth day of the third moon. Buddha's Birth, Enlightenment and Death A big celebration at Buddhist temples and pagodas with lively processions. Eighth day of the fourth moon. Summer Solstice Day (Tiet Doan Ngo) Keep the epidemics at bay with offerings to the spirits, ghosts and the God of Death. Fifth day of the fifth moon. Wandering Souls Day (Trung Nguyen) Second in the pecking order to Tet, offerings are made for the wandering souls of the forgotten dead. Fifteenth day of the seventh moon. Mid-Autumn Festival (Trung Thu) A fine time for foodies with moon cakes of sticky rice filled with lotus seeds, watermelon seeds, peanuts, the yolks of duck eggs, raisins and other treats. Fifteenth day of the eighth moon. Confucius' Birthday Happy birthday to China's leading philosophical export. Twenty-eighth day of the ninth moon. Christmas Day (Giang Sinh) Needs no introduction, this is not a national holiday, but is celebrated throughout Vietnam, particularly by the sizable Catholic population.