In their daily lives, Vietnamese people follow the standard 12-month calendar, otherwise known as the Gregorian or solar calendar used in the West. However, most of Vietnam's small village fetes and holidays follow the traditional Chinese calendar, which has 355 days and adds a "leap month" every 3 years or so to keep up with the solar calendar. Following the Chinese lunar calendar means that most holidays correspond with the full moon (on the 15th of each lunar month) or no moon (on the 1st); it also means that holidays fall on different calendar dates each year. For example: Tet, the Lunar New Year and Vietnam's biggest holiday, will be on February 14, 2010; February 3, 2011; January 23, 2012; and February 10, 2013.

There is a variety of regional celebrations and local festivals among the ethnic majority Vietnamese. Add to that the many disparate holidays and practices of Vietnam's 54 ethnic groups, and you have holidays left and right; any rural trip means a good chance of stumbling onto something interesting. Vietnamese are inclusive about their celebrations; Tet, for example, is a family holiday, but a few shouts of Chuc Mung Nam Moi (Happy New Year!) usually mean getting swept up in the fervor. Surrender to it.

Be sure to ask around about market days in the Northern Highland areas -- when a big, traveling goods market comes into town (usually Sun). Also look for the likes of modern city festivals, like the hugely popular Hue Festival. Below are the major national holidays and festivals.

January/February

New Year's Day. Everything but Dick Clark. January 1.

Anniversary of the Founding of the Communist Party. Nationwide. Celebrated everywhere; expect parade grounds in any city to be busy with cultural shows and speechmaking. Waving massive red flags in open-air shows in the evening is always the finale. February 3.

Vietnam Traditional Lunar New Year Festival (Tet Nguyen Dan): Countrywide. This 4-day national holiday, Tet, usually falls between January and February. The festivities begin on New Year's Eve and the first 3 days of a Lunar New Year, but most people celebrate for a week or more. It's a time to be with family members. The first day of the first lunar month (Feb 14, 2010; Feb 3, 2011; Jan 23, 2012; and Feb 10, 2013).

March/April

Festival at the Perfume Pagoda. Near Hanoi. Buddhists from all over Vietnam make a pilgrimage to the deep cave at the apex of this holy mountain at the half-moon of the second lunar month (Mar 30, 2010; Mar 19, 2011; Mar 7, 2012; and Mar 26, 2013).

Hmong Spring Festival. In the far north. Hmong populations across the north converge for colorful parades and market days. Fifth day of the third lunar month (Apr 18, 2010; Apr 7, 2011; Mar 26, 2012; and Apr 14, 2013).

Gio To Hung Vuong. This new nationwide holiday (added in 2007) commemorates the death of Emperor Hung. According to legend, Emperor Hung ruled over what is now modern Vietnam some 50 centuries ago. Tenth day of the third lunar month (Apr 23, 2010; Apr 12, 2011; Mar 31, 2012; and Apr 19, 2013).

Saigon Liberation Day. Celebrated nationwide with lots of parades and commemorative TV programming. Apr 30.

May

International Labor Day. The communist marching day around the world. Celebrations and parades in central squares nationwide. May Day, May 1.

Birthday of President Ho Chi Minh. Nationwide. Cultural performances and candlelight vigils are held across the country. The major sights in Vinh, Ho Chi Minh's birthplace, are overrun, and Hanoi's Citadel area, where Ho's body is held in state, is mobbed. May 19.

August/September/October

Tet Trung Nguyen. Nationwide. A time to give thanks to the ancestors. Families gather, remember those who have died, eat, and visit grave sites. Half-moon of the seventh lunar month (Aug 24, 2010; Aug 14, 2011; Aug 31, 2012; and Aug 21, 2013).

National Day. Celebrates the rise of the Socialist Republic of Vietnam. Local parades, pomp, and circumstance. Sept 2.

Do Son Buffalo Fighting Festival. Near Haiphong. A riot for everyone (except the buffalos). The ninth day of the eighth lunar month (Sept 16, 2010; Sept 6, 2011; Sept 24, 2012; and Sept 13, 2013).

Mid-Autumn Festival. Nationwide. This colorful celebration is a popular one for kids, with dance and special sweet cakes. Half-moon of the eighth lunar month (Sept 22, 2010; Sept 12, 2011; Sept 30, 2012; and Sept 19, 2013).

December

Christmas. Nationwide, but most widely celebrated in the south, where Christian populations are largest. Although Vietnam's recent plunge into capitalism means more and more American-style Santa-focused decorations and shopping in the major cities, you can still expect some Ho Ho Ho Chi Minh style. Dec 25.

For an exhaustive list of events beyond those listed here, check http://events.frommers.com, where you'll find a searchable, up-to-the-minute roster of what's happening in cities all over the world.

The Tet Holiday: "Over the Rice Field & Through the Jungle . . ."

Imagine an American Thanksgiving, Christmas, New Year's Eve, and Easter all rolled into one -- that's Tet. This megaholiday on the Vietnamese calendar is a time for pilgrimage to the family stamping grounds. Everyone, including the many young Vietnamese who have left the rice fields for work in the big cities, goes home (travel is a nightmare and best avoided). Food is the focus, and everyone hustles home to try Grandma's chung cakes -- a small square cake made of glutinous rice -- after a real feast of down-home cooking (regional variations are many). This is a time to honor ancestors; offerings of fruit and flowers, whole feasts even, are placed on family altars. The 23rd day of the 12th lunar month hosts a ceremony of farewell for last year's "Kitchen God." The 29th and 30th days are a time to say farewell to the old year and hello to the new, with all the fanfare and hoopla you can muster; streets are crowded with motorbikes, and the rice wine and bia hoi (local draft beer) flows freely. Folks go a-visiting on the first day of the lunar new year, sharing food and fellowship among neighbors. Tet is also a celebration of Vietnamese strength and autonomy. On the fifth day of the Tet holiday, people raise a glass (or two) to freedom fighter Quang Trung, who defeated the Chinese at Dong Da near Hanoi, and spurred them on with cries of, "And then we'll go home for some of Grandma's chung cakes!" Bonsai!