Smiling in the buff at Orpington

It is like any other holiday camp. The atmosphere is restful, punctuated by the chink of beer glasses and the quiet chatter of people on park benches. The exception, however, is that everyone is naked.

If you wander down the lane past the entrance to Brocken Hurst, the Naturist Foundation's 50-acre country estate just outside Orpington and only two train stops from Victoria, there's nothing to indicate that up to 1,000 undressed people could be ambling around inside.

'It's a bit strange, if you ask me, my taxi driver said as he dropped me off. 'Wandering around like that in front of children. I wouldn't do it.

Christine Ashford, general secretary of the foundation, a generously proportioned woman of 46, meets me at the top of the drive. Naked, she holds a small towel over one arm.

There are no changing rooms (something I should have anticipated) so I step out of my shorts and walk away. I had been reliably informed that it's rare for male first-timers to get an erection.

'We get all sorts here - plumbers, priests, politicians, policemen,' said Ms Ashford as we toured the grounds.

'People mix freely here. We don't have to keep up a persona. All the signals are taken off. The difference is very striking when you see people coming straight from work in suits, and you know them naked.'

Ms Ashford came as a visitor once and stayed on to become caretaker and administrator. Her family now lives within the estate, and they lead a paradisal lifestyle. She is enthusiastic. 'When you take your clothes off, you take off the stress of life. It's healthier and more hygienic. The skin can breathe. I don't need to justify why I do this. It's up to the world to justify why, on a day like this, they do wear clothes.'

Some might argue that nudity itself is a good reason for keeping your clothes on. Naturists, I see, come in all ages - and sizes. I overtake a couple resembling a large pink sofa, their cushions of cellulite wobbling. Elsewhere, reedy octogenarians pick their way like storks through the fruit bushes.

They all have one thing in common: a permanent smile. Unnerving. I adopt an inane grin in return and move in what appears to be the prescribed casual style.

Convention also requires that you sit with your legs as wide open as possible to show you're completely relaxed. Even though I can see every inch of the bodies facing me, a formal etiquette underlies the easy atmosphere. You should, for example, always put a towel on a seat before you sit on it - 'just in case someone's got something they shouldn't have,' I'm told.

The estate offers Londoners the chance to strip off without being arrested. Nude sunbathing isn't allowed by the Corporation of London. The nude stretch of Brighton beach is the only other place most Londoners know about.

Public nudity is a thorny issue for the police. 'If someone chose to sunbathe naked in their back garden and a neighbour complained, it would be unlikely that the person would be arrested, but it may be that we would give them some words of advice,' said press officer David Jervis of New Scotland Yard.

'Of course, we might give the neighbours words of advice too. But there's no specific policy on nudity.'

Whatever the status of the law, I quickly learn that you don't ask what naturists do in the outside world. One female headteacher I speak to fears she would be dismissed from her job if her school found out. 'I would just lose all authority. People would assume I was unfit for the job.'

However, some are eager to speak up. Phil Jenkins, 50, is a supervisor on a North Sea oil rig. He has brought his family to Brocken Hurst for the past 17 years, paying up to pounds 1,000 a year for the privilege of visiting his caravan.

'My job is very stressful. I can leave it all behind at the gate. I become a different person here.' Phil wears a baseball hat, fluorescent trainers and gleaming white teeth against an all-over tan. 'When I go back to work, the blokes always notice how great I look.

'Everyone here is equal. There's no such thing as ugly here. There's a woman here with a colostomy bag. She wears different coloured covers just for fun.'

For his 24-year-old son Graham, a hesitant man with thick-edged spectacles, the cheap beer and sports are the main attractions. He has trouble convincing girl friends to join him: 'I tend to get funny looks when I first suggest it to them.'

Perhaps they've heard of the great To Shave or Not to Shave debate. The keeping or removing of pubic hair is being debated in naturist circles. The latest edition of Health & Efficiency, the monthly naturist bible, features a group of Dutch nudists who insist that would-be members reach for the clippers immediately.

It's impossible to see whether Ms Ashford is of the same persuasion - it's impos-sible to see past her stomach - but her husband's waif-like body is devoid of hair.

At Brocken Hurst, sex is never mentioned and applications are vetted to weed out those with suspect motives, although how this is done is not explained.

Families are welcomed, while single men pay a higher levy than single women. There is one open day per year, where naturists are subject to the eager gaze of the British public, if only to prove nudity is a virtue. But can social nudity ever be entirely innocent? 'We've got high moral standards,' Ms Ashford insisted. 'It's nothing to do with being exhibitionist. There's a lot of hypocrisy about being naked in public in this country.'

Frankly, I don't need reminding. Being a new face - and body - I feel eyes assessing me all the time.

But although I am due to leave, I want to stay on, an unexpected convert to the sense of total freedom that being naked brings. It is with reluctance that I put on my clothes and walk down the drive.

The Naturist Foundation, Orpington, Kent BR5 4ET (0689 871200).

(Photograph omitted)