Looking for a picnic spot near Trouville beach last month, we clambered over the Normandy rocks and found the perfect cove. Only someone else had found it first. A man, perfectly naked, lay bronzed and burning on the sands. Quite put us off our saucisson and peaches. If you have grown up on British beaches under cagoules, windcheaters, balaclavas, mittens and two layers of socks - "There's a bit of sun behind that cloud, I'm sure of it" - then the French coast comes as a shock. Tops off, trunks down, not a tan line to be seen from Brittany to the Riviera. Talk about Gallic cockerels.
Nudism, once the holiday habit of embarrassing French parents - the hippyish, soixante-huitard generation - is being taken up by their children and grandchildren. According to the French Naturism Federation, there are now 2.7 million nudists in the country. One can sign up for naked yoga, naked singing, naked gym classes, naked bowling, and - heaven help any woman who has cast off her sports bra - naked trampolining.
The picturesque Bois de Vincennes, to the west of Paris, has a designated nude area. At the nudist restaurant O'Naturel you can dine on snails in garlic cream and duck-fat frites. Don't drip the duck fat on your lap. The film Normandy Nue ('Normandy in the Nuddy') has been the year's surprise cinema hit. Think Calendar Girls with cows.
The French don't lack inspiration: Cezanne's bathers, Corot's nymphs, Boucher's lovely rococo bottoms, Manet's Dejeuner sur l'herbe... Any sylvan glade, any shady pool will do: petticoats off and frolic for all you're worth, girls.
This being France, intellectuals are trying to explain the national state of deshabille. Nothing so simple as it's nice to be naked. Historian Sylvain Villaret suggests: "The practice of naturism is linked with periods of great upheaval. Nowadays, people are looking for meaning and many turn to causes like responsible consumption, environmental protection or social solidarity, especially the young. The values of militant naturism are in accord with these causes." A fine bit of philosophy to contemplate as you trampoline in the buff.
Where does that leave a buttoned-up Brit contemplating a summer holiday in the Loire? Some of us are too shy for skinny dipping. As I tried on maillot after maillot last week, these lyrics from Peter Sarstedt's Where Do You Go To My Lovely played in my head: "When you go on your summer vacation/ You go to Juan-les-Pins/ With your carefully designed topless swimsuit/ You get an even suntan..."
Would I, could I, dare I bare all on the beach? Oh, for the cover and comfort of a cashmere cardie on a bright, cool, breezy day in Norfolk. I only have to look at a publicity photo from Love Island and the female contestants' itsy-bitsy-teenie-weenie-navel-grazing-slashed bikinis to long for a cold snap.
The French have a saying, equivalent to our "Ne'er cast a clout till May be out." It runs: "En avril, ne te d'couvre pas d'un fil/ En mai, fais ce qu'il te plait." That is: "In April don't take off a stitch. In May you may do as you wish."
As for a July heatwave... The forecast is for 35 degrees in Paris this week. I predict bare buttocks in the Bois and topless tanners in the Tuileries. Tourists: try not to blush. And remember, it's fine to keep your clothes on - especially if you're British.
The Daily Telegraph, London