Welcome to Glastonbury-on-Sea: Jonathan Sale describes his family's annual descent on a Cornish campsite in a flurry of surfboards and muesli

Toddlers, teenagers, parents, grandparents: on the family campsite where we stay, most of the family is mine. This summer we were pushing 40 - our nuclear family, the wife's sister's nuclear family, nephews and nieces and their partners, our great- nieces and assorted friends.

There are large tents, moderate tents and 'pup' tents into which teenage children creep when the pubs and even the beach parties have closed. We make up a Bosnian enclave among the rest of the campers at Crantock, near Newquay, but the only sniping is verbal - at the ghetto blaster eight tents away.

We have been pitching our tents at Treago Farm for exactly 20 years, since the first summer holiday of our first child. Her grandparents, who came with us, have passed on to the Great Campsite in the Sky; but her cousins have produced the next generation of tent toddlers who, as dusk falls over the Cornish landscape, can be heard not going to bed.

All these relations are on my wife's side of the family. My own side has always been addicted to bricks and mortar: I come from a long line of bed-and- breakfasters. My brother popped into the site one day years ago for a walk to the beach, but then zoomed off to a holiday cottage. After an unfortunate experience in the Scouts, I used to feel that canvas was all very well for yachts but made a poor roof.

My wife, by contrast, had a more privileged background - as a happy Guide. She persuaded me to join her in acquiring a tent so large that you could have let out the west wing to another family. In case I had uncontrollable longings for walls that did not flap, her parents parked their caravan alongside as a bolthole for our first holiday.

I never needed to bolt. I took to camping like Kenneth Williams and Frankie Howerd combined. It was partly the situation, in National Trust territory among fields and a common that rolls up to the horizon. It was mainly the free fresh air that passes as easily as a ghost through even a zipped- up sleeping compartment. I eat my muesli outside and feel that instead of merely writing about the environment, I have graduated to become part of it.

The children clearly think all that is a lot of hot, rather than fresh, air, to judge by their eagerness to spend their evenings in pubs as smoke-filled as the epicentre of an Australian bushfire. What they prefer is to chill out with folk who use words like 'chill out'; that is, the cousins and friends they meet here for a fortnight every year. If they came with only their nuclear family, they would soon start complaining. And then go off for a holiday somewhere else.

The older cousins spent summers elsewhere for a time but now return with their own youngsters. One of the prodigal nephews used to entertain us at beach barbecues with his version of 'Mull of Kintyre'. Accompanied by carefully untuned guitar, it was far funnier than the Paul McCartney version, especially since at the climax of the number Jon threw dried cowpats over his audience.

In the intervening years, he switched to the fiddle and formed a radical folk- rock group known to the charts and the Glastonbury Festival as The Levellers. His presence causes ripples among the kids on the beach; the first time he went surfing, a fan on the same wave asked for his autograph. Jon also helped swell our numbers, bringing not only his own partner and children but also Simon his fellow Leveller, and Steve who does the band's lighting. Our little patch of the field has become Glastonbury-on-Sea.

Has Jon been spoilt by success? Yes. He refuses to perform at our barbies any more; we uncles and aunts cannot offer Musician's Union rates. Simon, though, when handed a guitar and a pint (in reverse order) agreed to sing the odd number at the campsite's bar, as cameras flashed and camcorders whirred.

Apart from him, there is much to listen to in Tent City. Sound travels unimpeded through canvas; just because your relatives can't see you, doesn't mean they can't hear you. It is like being permanently bugged by the Special Branch.

'Is there any chance of an advance on next month's allowance?' asks a teenager. From not just his own tent but from three surrounding canvas homes there comes the automatic parental chorus of 'Fat chance]'

The kids now asking for cash were as babies equally embarrassing - by night. On the first day, there is a frenzied jockeying for position to avoid the pitch next door to whoever has a baby liable to let rip at 3am. Since we live in different parts of the country, this involves much calculating of relatives' relative distance from Newquay and hence their estimated times of arrival.

You can say what you like about the wife's brother-in-law (preferably not when you are in your tent), but I have to admire the selfless way he stopped to help us change a tyre on the hard shoulder of the M5. I was so grateful that I resisted the temptation to let down one of his tyres, which would have given me a head start in the race for a baby- free pitch.

Once, I was in such a hurry that I forgot to tighten the nuts on the collapsible trailer. The nearside wheel came off, overtook the car and reached Cornwall first.

It tends to be the disasters that live on in the oral history of our canvas holidays. There was the Year of the Virus, when we all went down with a mysterious sickness believed to be connected with Newquay's practice of emptying its toilets into the sea. Round the corner at Crantock, we know that our beach would benefit from a current that flowed the other way. This year we have taken out family membership of Surfers Against Sewage.

Then there was the Year of the Hedgehog, when we pitched on what turned out to be a small mammal's motorway. All night long we heard the tramp of Mr and Mrs Tiggywinkle marching through the tent. By about 2.30am the charm of this had worn off, so I constructed a barricade of surfboards, which resulted in the banging of snouts on wood and desperate hedgehoggy oaths.

One night the defences were breached by a prickly intruder which began rummaging around in our provisions. I scooped it up in a bucket and by the light of the moon deposited it on the Cornish Coastal Path that leads to Land's End.

You can go off wildlife: 1993 was the Year of the Snail or, in the tent next door, the Year of the Small Slug; 1994 was the Year of the Dingo, so named after the diminutive, slinking dog Jon brought with him. It catches stones in its teeth with a clunk terrible enough to bring dentists rushing from behind the rocks.

Apart from the Dingo, any life-forms are liable to end up in the pot. This annoys vegetarians like my daughter. Camp cooking in general is a universal sore point, largely because of our envy of the culinary skills of the wife's brother-in-law.

After a day spent analysing rock samples (he is a science teacher) he produces, on a couple of gas rings, a cordon bleu dish that the rest of us could not match with a proper oven, and ingredients provided and chopped up by Keith Floyd.

His skill leads to unkind comparisons being made, particularly at the communal eat-ins when we all cobble together something vaguely edible. I often provide a supermarket salad, modestly informing fellow eaters that I removed the wrapper with my own hands.

The wife's brother-in-law catches a lobster himself and serves us a magnificent homard a beau-frere with all the trimmings but no bits of grass.

One year I pulled out all the stops, opening several tins and checking that their sell-by dates were not too long expired. Proudly I presented the resulting dish to the waiting relatives.

'Ah, pigswill,' remarked one. She meant it kindly and to prove it she added, 'I'll have seconds.'

My self-confidence returned. That's what relatives are for.

(Photograph omitted)