Here in the Herefordshire Marches, the heartier ones have already descended. Holy Week will bring more of them to our hedgerows, chattering in their distinctive calls, vivid in their plumings. April is not only about daffodils and flowering blackthorn. It is not only a time for the first mow and hefty tractors flattening fields. Amid the early oil beetles, the advance parties of swallows, the tortoiseshell butterflies and the low-drone bumble-queens, something else stirs.
See? Over there, behind the tumescent crab apple trees, at the far end of the meadow. Lo and behold, through the morning mist, triangular shapes have appeared overnight. Tent poles at dawn: the campers have arrived!
According to the Camping and Caravanning Club, last Easter saw record numbers of domestic tourists laying temporary claim to a square yard or two of Mother England. The club's 110 sites across the country saw a 50 per cent rise on 2009. This year, with Easter later, money tighter, the recent weather so bright, camping's boom is likely to continue. In 2008, more than £1bn was spent in Britain on tent and mobile caravan holidays. It could be twice that this year. Easily.
What is it about camping? After all, property developers have gone to a lot of trouble to build budget hotels and holiday parks (sorry, parcs). That nice Mr Stelios will fly us to southern Italy for the price of a reasonable curry. We are always being told, are we not, that the 21st-century generation is pansy-soft, hooked on mod cons, stuck in a computer rut. Maybe that last point helps to explain it. We hanker for something simpler; if not for caveman rawness, then at least for a nylon shelter somewhere rustic in the shires. Away from the ruddy BlackBerry. Somewhere the office will not be able to find us.
Non-believers say camping must so often be "such a disappointment". All that rain. Things going wrong. But disappointment is a vital ingredient. If the camper does not experience discomfort he or she will feel short- changed. You step outside your tent first thing in the morning and find a gun-metal sky looming overhead. Do you pack up and go home? You do not. You summon the country air deep into your lungs and say, "Cor blimey, it's cold. Shall I make a brew?"
You discover that you have left your eating utensils – worse, your corkscrew – at home; you step first in a near-liquid cowpat, then on a stinging nettle; you arrive late at night at some apparent rustic idyll, somehow erect the tent ("There! That wasn't so bad!"), and then wake to the sound of pneumatic drills and the dust of gravel lorries from a major arterial route construction site just on the other side of the hedge. Do you strike camp and leg it for the nearest Premier Inn? Not if you are a real camper.
Such experiences make camping what it is. They strengthen the camper's soul, stiffening it as surely as does the flexible, aluminium rib in the corner of that Sir Chris Bonington-style bivouac you bought from Millets in a sale. Camping nourishes our resilience. It makes us as tough as overcooked liver. It is independent. If you have five pints of ale in a country pub and then stagger back to your Vango Titan 2-Man tent, there is nothing the law can do to reprimand you.
Camping used to smell of wet canvas. Now there is the rustle of the hi-tech synthetic materials they use in anoraks and sleeping bags – the sort of rustle Ray Mears makes when he is crouching in some perilous hole of the global wilderness, within yards of a deadly carnivore.
Rucksacks are not as spine-snappingly heavy as they were, but is there not still, in the way they clank – particularly if you have your saucepan hanging on a length of string like some Oregon pioneer – something martial and manly about their bulk? You may only be traipsing along the Wye Valley walk, but you can still imagine you are one of the Heroes of Telemark, sticking close to Kirk Douglas. Camping feeds the imagination. It freshens your faculties and fantasies.
We have the Victorians to thank. The first to latch on to recreational camping was Thomas Hiram Holding (1844-1930) who developed a taste for it while crossing the American Wild West with his parents in the 1850s. In 1901, Comrade Holding, by now a tailor back in Britain, designed the first easily folded tent. I say "easily folded", but campers know there is no such thing. It takes years of practice to fold a tent, and there is only ever one person in a family who knows exactly how to do it.
Hiram formed a club for tent-minded cyclists and mounted expeditions into the shires and beyond. In 1906, the Association of Cycle Campers opened its first campsite in Weybridge, Surrey. Camping was given a further punt upfield by Robert Baden-Powell, for whom bliss was a night round the camp fire in a pair of shorts with a troop of Boy Scouts.
Camping regained popularity after the Second World War as mobility increased and families started to take holidays. Prudish hoteliers also did their bit for camping. Young unmarrieds might not have been allowed to share a room in guesthouses, but there was nothing to stop them snuggling up together under canvas. This ooh-er-missus angle was reflected in the 1969 film Carry On Camping.
Barbara Windsor hiding her modesty is the classic image of English camping, but the subject's best artistic treatment is Mike Leigh's 1976 play for television, Nuts in May. Keith and Candice-Marie Pratt are making an expedition to Dorset. Keith is a martinet – every camping holiday has one of these – and is determined to find the ultimate idyll of peace. Candice-Marie is more easygoing and can't see the problem with locations that Keith keeps rejecting.
Leigh catches the itchiness of camping – and I don't mean the midge bites. Campers, like children seeking gold at the end of a rainbow, are destined ever to hanker for something. They always suspect things might have been just a little more perfect. We should have put the tent there. We should have brought the spare Calor gas cylinder. I told you to remind me before we left home.
In the case of Keith Pratt, it is the intrusion of 1970s music and attitudes on his ideal of a more innocent, bucolic England. He wants to spend his camping holiday singing folk music and enjoying nature. This keeps being shattered by noisy campsite neighbours who listen to pop music. Camping has a groovier side these days, thanks chiefly to rock festivals. At Glastonbury, Ledbury's Big Chill, Reading and their ilk, camping is as much a part of the experience as the music or the mind-altering substances. In the days leading up to Glastonbury, you see hundreds of youngsters heading towards Somerset with their bedding rolls and their tightly packed tents and their expressions of gleaming excitement. A few days later you see the same crowds, but they have been transformed. In some ways they can look like a retreating army, muddied, crumpled and distinctly whiffy. But they have been through something. They have known communal discomfort. They have camped!
Sir Alan Ayckbourn is obviously a sometimes camper. His play Living Together has the line, "I don't honestly think you can possibly share a small tent with someone's who's ebullient." The uninitiated may think of camping as an activity in which "happiness is compulsory". It is more complicated than that. Happiness is to be found, yes, in the expectation of the camping holiday. It may also be mined from nostalgia after the holiday, for the sizzle of breakfast bacon from the camp frying pan, the clink of metal poles, the sound of the tent's flanks rippling in some character-forming gale. Campsites are incomplete without at least one over-enthusiastic maniac who leaps out of his sleeping bag in the morning to run on the spot and or do star jumps, but they are the exception. Most campers have a very English melancholy streak. They know that comradeship flows from discomfort. If it isn't hurting, it isn't working.
In the early 1970s, my parents used to drive us to the Costa del Sol every summer in a wheezing old Vauxhall and we would camp en route – a trickier proposition in those days. My dear father would grapple seemingly for hours with poles, guy ropes, groundsheets and straying toggles, saying "thang yew" with methodical determination as each section of wooden strut clicked into place, each butcher's hook sank into hard, continental soil. At the end, he would step back to say, "There, perfectly straightforward!", only for one of us to fall over a stay and wreck the masterpiece.
Most of us will have camping memories, many composed of the sound of plip-plop raindrops on the tent. Mine include cooking Vesta curry on a beach in Lesbos, and my first tent which had a separate groundsheet which allowed the rainwater to whoosh straight though the tent.
Last weekend, our 13-year-old son went kayaking on the Wye with a couple of other lads and their dad, a military man. They camped a night in Ross, with campfire porridge for brekker and a splash of freezing water on their faces. "How was the night?" I asked. "Freezing," said my son. "We didn't get much sleep and it was really uncomfortable." Would he like to go again? Not a second's hesitation. "You BET!"