The best places for outdoor swimming in Europe

Late on a summer afternoon there's a favourite spot on the river where the kingfishers dart and otters play. It's a wide, clear pool with draping willows and meadow all around. There's a pebbly beach for those who like to tip-toe in, and a tree swing and deep bit for those who like to plunge. I am of the latter persuasion, so with a leap and a dive I'm under the surface, rising in a riot of bubbles. I breast-stroke about, taking little sips of the pure, sweet water as I go, admiring my frog's-eye view. Cow parsley towers above, water buttercups tickle my feet and it's mossy and soft as I climb out and stand in the sunlight, dripping and elated.

The popularity of wild swimming has grown over the past few years, inspired in part by keen-eyed naturalist Roger Deakin - almost a latter-day folk hero now - who set out to swim across Britain via its network of rivers, lakes and waterfalls. Wild swimming is the new cool, and not just because of the invigorating temperatures. There's something both innocent and cheeky about skipping around water meadows in swimwear. It's revitalising and addictive - and it introduces you to hidden parts of the countryside you may think you know well.

Wild swimmers are generally friendly and easy to recognise out of the water. We're the ones shivering under jumpers with strands of river grass in our hair, or grinning over mugs of steaming tea in the beach café. Excursions are cooked up on Facebook, stories and maps shared. If you want to try a spot of natural dippage yourself, there are a few points of etiquette to remember. It's not the same as naked swimming, so don't treat this as an excuse for exhibitionism - and remember that canoeists, fishermen or birdwatchers could appear from behind the bushes at any moment (possibly with binoculars). Don't be so kit obsessed you bring North Sea-style wetsuits: it makes the rest of us feel cold and doesn't look right as you prance about among the cowslips. Try to avoid rivers after rain or drought, and give canals a wide berth too, unless you're looking for shopping trolleys. When jumping, check the depth first. And finally, make sure you bring a proper picnic with a rug, chilled wine and smoked salmon. Wild swimming burns off fat, and you should always stock up with rations when heading out for an adventure.