This doesn't happen every year. From 1987 to 1990 the canals were only fit for ducks. But occasionally the ice passes the council test: over the course of two weekends in 1991 more than 10,000 people skated, walked and crawled past the windmills, restaurants and ice-bound locks from Bruges to Sluis.
It was a chance remark at a party that alerted me to the great Belgian skating marathon. With reflexes speeded by the temperature, I headed round to the nearest skate shop, bought a new set of Hockey Skates for pounds 50, borrowed a car and headed for the Continent. As the ferry cut through the still, cold air, I sat steamy-warm inside, while truck drivers played cards in an atmosphere of shared adversity.
The Continental attitude to the big freeze is a little different to ours. The British authorities tend to discourage skating. Yet over in Belgium, as soon as it freezes, people are out there skating away for all they're worth. On the way from Ostend, driving through a world waking just before dawn, I caught sight of a solitary skater describing lonely circles on a roadside canal.
It was probably his only chance to skate in peace. As the day wore on, more and more people joined in, carpeting the canal with bright snow clothes and adding the bubbling noise of a nation in party mood. From a distance, the canal surface resembled a trail of vibrant ants. Close to, it was much less sinister and much more fun.
Brueghel might have scraped the ice from his palette at the sight. All cars seemed to have been frozen in their garages by the weather, and the entire population had taken to the ice in an eerily silent world of white fields and frost-rimmed avenues of trees. Parents pulled children on sleds, grandparents hurtled past at speed.
Meanwhile, unfamiliar in new skates, I steered an erratic course, one eye on the way ahead, the other spellbound by the view. Crowds faded, within a few hundred yards, into a haze where the glow of the sky blended with the gleam of the land.
Border formalities might be a thing of the past, but cultural differences live on in Europe, and at skating speeds - especially mine - these are unmistakable. The traditional skating route runs along the canal and covers 34km (21 miles). Over this distance the atmosphere changes dramatically. From the crusty respectability of Bruges, the tree-lined canal cuts through picture-postcard scenes of rural Belgium, windmills glowing faintly through the haze amid restaurants that advertise the fact they serve eels. Top of the twee - and a central place to stay overnight - is the village of Damme, where flower baskets hang from houses that look as if they have been coated with sugar icing. Out in the fields the atmosphere is already relaxing fast. Vendors set up stalls on the ice, using gas fires to heat "opwarmers" of hot wine.
The last traces of quaintness evaporate over the border. The small town of Sluis is the nearest point for Belgian tourists to rub shoulders with their Dutch neighbours. The canal cuts straight into the town centre. Usually this radiates the cosmopolitan ambience of a historic port, complete with dark-watered canals for disposing of double-crossing diamond smugglers. In winter, the waters are turned into hockey ground, village green, and meeting point. On top of the rims of the stone canal walls, high above circling skaters, shops line the narrow waterfront streets, selling fine cigars imported from former Dutch colonies, dodgy videos and plenty of beer. Whatever you make of Sluis, the gliding ice-journey here can't fail to appeal.n
By sea, the two closest links are from Ramsgate to Ostend on Sally Ferries (0990 595522) and from Hull to Zeebrugge on North Sea Ferries (01482 377177). By train, the special Eurostar bus link from the station at Lille to Bruges operates only in summer, so is of little use for skaters. You can either travel on a roundabout rail journey via Brussels, or go by sea; the rail/Jetfoil link from London to Bruges is about as quick as Eurostar. To reach Damme, take bus 799 from Bruges railway station.
Belgian tourist office: 29 Princes Street, London W1R 7TG (0891 887799). In Damme, the tourist office is in the main square (00 32 50 35 33 19).