What do a duke, 800 rubber bands, 26 miles of rural Leicestershire, 2,000 slices of cake, 100 square metres of cardboard and lashings of mud have in common? It might sound like a bad joke but they’re all vital ingredients of the Belvoir Challenge, an extremely successful fundraiser for a small rural primary in the picturesque vale of Belvoir, north-east Leicestershire.

The event is a cross-country marathon following green lanes, footpaths and canal banks in the Leicestershire countryside, some of it the private domain of the Duke of Rutland, who allows runners and walkers to cross parts of his estate on the big day. In recent years, several hundred people have taken up the challenge, tagging themselves with numbered rubber wristbands like those used in public swimming pools, to identify them at checkpoints.

It all started 13 years ago, when the Partridge family (not the cheesy 1970s singing clan, but parents with children at the school who were keen distance walkers) persuaded Harby Church of England primary school to become involved in a long-distance running or walking event that would also generate funds for the school. The headteacher, governors and parents agreed to take part, although many may have had second thoughts when a date was set for late February.

The plan for that first Saturday morning was to use the school as the start, registration point and first tea stop for hundreds of hardy competitors, each paying a fee. The route would wind its way from the school around the Vale of Belvoir with cakes and refreshments provided by parents at each of the checkpoints. The competitors would return to school for hot soup, crusty bread and apple pie and cream. (These days, the website warns competitors that “it’s one of the few events where you can actually put on weight”.) Well, the day arrived, along with more snow than the vale had seen in 20 years. Surprisingly, so did more than 100 hardy souls, many of whom could have been forgiven for thinking they had entered an alpine cross-country skiing event. The run raised a tidy sum and has been put on every year since (whatever the weather - we never cancel), raising pound;45,000 to date.

Three years ago organisation passed to the Friends of Harby School and the Vale Striders running club, and its popularity has grown enormously.

Running and walking magazines promote it, clubs pencil it into their calendar while some competitors are just talked into it after a couple of jars at the local pub.

Last year more than 800 runners and walkers competed in the two distances (15 and 26 miles - pound;7 and pound;9 entry fee respectively), raising pound;6,000 for school funds. (2001 was even more impressive, with pound;8,000.) The school has benefited hugely, spending the money on improving teaching areas, enlarging the playground space, providing activity trails, creating kitchen areas and, this year, we hope, supporting IT provision.

The event relies heavily on the support of parents, the community and local and national businesses. As the day draws near (this year’s event took place last Saturday) the village prepares itself for an invasion of the bobble hat and lycra brigade, which doubles the population for around 10 hours. Ex-pupils turn up and the Partridge family is still involved, storing the cardboard sheets used to protect the floors of the school and village halls, and running checkpoint 4.

Volunteers must perform a range of extreme sports to ensure the event takes place: trekking the sodden countryside in the depths of December, route-planning, flapjack-baking, marquee-wrestling in the early hours, and late-night scrubbing and mopping to make sure the school is back to normal for Monday morning.

Harby’s 69 pupils also get involved, designing the T-shirts and certificates that are presented to all those who finish within the 10-hour time limit. And yes, most do, despite being weighed down by mud and mountains of grub. The children also take part in their own mini Belvoir Challenge held around the same time (this year it’s February 21 - today) with more realistic distances of between one-and-a-half and six miles, but still involving copious amounts of mud.

The event has moved on in 13 years and now boasts its own website, where you can register your interest in next year’s event and gaze questioningly at those who took part in previous years. Don’t let them put you off - it’s a grand day out.

For more details of the Belvoir Challenge, go to www.

belvoirchallenge.fsnet.co.uk. Richard Simpkins is headteacher of Harby C of E primary school, Melton Mowbray, Leics