In Belgium, the tradition is for huge, elaborately organised events and excess in all things - from drinking to political satire to the liberal distribution of sweets to children lining the parade routes.

Small celebrations take place all over Flanders, but three haul in the Carnaval faithful from around the region.

The oldest
Herenthout, in the Kempen country of Antwerp province, calls itself the oldest Carnaval stoet in Belgium, a claim endorsed "until proven otherwise" in 1978 by then-Flemish culture minister Rika De Backer. According to the Carnaval's unofficial historian, André Cambré, the statement came after the king's visit to Aalst's 50th stoet led to "a whole polemic, with questions in parliament".

The first Carnaval stoet in Herenthout dates to 1882, when the well-known actor Flor Hoegaerts left the theatre in his costume and, with friends and onlookers in tow, rode a white stallion round the town square. Later in the evening, lubricated with drink, the participants decided they would do the same the following year, and so the event was born. The municipal authorities only gave their imprimatur, as well as funding, in 1893, apparently at the request of "a large number of townspeople". Apart from the war years, the parade has taken place without a break since then. The special character of Herenthout, Cambré says, is its basis in theatre. "About 40 to 60 groups take part, stopping every 50 metres to put on a short piece of street theatre. That goes on for about four hours."

Herenthout, like other Carnaval towns, elects a Carnaval Prince each year who presides over the festivities, together with his Nar, a sort of jester or Fool, who performs somewhat the same role as the Lord of Misrule during the pagan feast of Saturnalia (with which Carnaval has much in common, aside from the date).

This year's prince is Rudy Dieltjens; his Nar is his twin brother Luc. Prince Rudolf is well-placed to lead the parade: his float will be built by students at the Scheppers Technical Institute in Herentals, where he trains future electricians. "The students came and asked me what exactly I want, and I told them to show me what they can do. I'll be standing up there later, but only thanks to the work of a lot of young people and colleagues."

The biggest
The Aalst Carnaval is without a doubt the most famous in Flanders, and it's fair to say that, while the Aalstenaars consider the onion to be their emblem, for most other people they're represented by the enormous turn-out on Carnaval weekend and for the elaborate and politically tinted floats that make up the annual stoet (parade).

Historian Wim Beelaert wrote his thesis on the Aalst Carnaval for his degree from the University of Ghent, and maintains a detailed website (www.vastenavond.be) on the history of the event. He dates the first stoet to 9 March 1851, when it was organised by a traders federation. The event didn't become an annual event, however, until 1923, when it received an official sanction from the municipality. "Then there were 23 groups that rode through the city. The initiative was an immediate success," he says. This year's parade counts as the 83rd.

According to Ann De Block, a conservator at the city museum, Carnaval in Aalst is a manifestation of the highly active social and associative life of the town. Aalst is a place with deep working-class roots and a tradition of labour activism dating back to the 19th century. The same social cohesion helps bring people together in the dozens of large or small groups who work all year round to prepare the festivities of Carnaval.

"The groups are very close-knit, and there's a huge feeling of working together," says De Block. Aalst's Carnaval is included in Unesco's list of notable examples of intangible cultural heritage.

The one on the coast
Blankenberge claims the first Carnaval "cavalcade" in 1875, with men going in costume from café to café and being pelted with snowballs by children. Later, the event achieved such renown that special trains were laid on for visitors from Bruge and, in the days before the coast tram, from Heist.

But the Catholic authorities in the town weren't happy with the unruly nature of the event and managed to bring enough pressure that the cavalcade was boycotted by the municipal authorities (masks were even banned from 1918 to 1923). But it went ahead all the same. In the end, the main impetus for the Carnaval parade came from the Casino, mindful of the need for winter tourist income. The event has been an annual occurrence since 1952, despite severe flooding at the coast in 1953.

Pictured: Herenthout, the longest-running Carnaval in Flanders "until proven otherwise"

What's on when

Carnaval activities go on for weeks in these three towns, but the big parades happen this weekend

Herenthout: The stoet in Herenthout - complete with street theatre - takes place twice, on Sunday 6 and Sunday 13 March - strategic, so it needn't clash with another town. There's a fancy-dress ball on Monday 7 and a Children's Carnaval on Tuesday 8. Herenthout is also organising a poetry contest in the run-up to its 121st stoet, and visitors can see the winning entries on banners hung from the church tower and the public library, as well as printed on beer mats. (It is still Carnaval, after all.)

Aalst: The big stoet is on 6 March, and if you've never experienced it, now's the time, when it's slightly later in the year than usual and perhaps not quite so freezing cold. The famous Voil Jeanettenstoet (where men dress up as hideous, bare-breasted women) takes place on Tuesday 8 (Fat Tuesday). On Saturday 12, there's an afternoon of fitness, meditation and voice exercises to get participants in the recent stoet back into shape and on the road to next year. That evening is a champagne reception, dinner and sing-song, followed, somewhat optimistically, by morning gymnastics at 5.00 on Sunday morning.

Blankenberge: Blankenberge's official stoet is Sunday 6 March, and it also has its own version of the Voil Jeanettenstoet (cross- dressing is one of the oldest traditions of Carnaval) on Fat Tuesday, 8 March. At the same time are Carnaval games for kids (hopefully in some distant part of town). On Saturday 12, there's a dip in the icy sea from the beach west of the pier, followed in the evening by fireworks on the beach and the burning of an effigy of last year's Prince, all in good fun of course.