1. Snowdonia's stunning tarns
Tarns – or llyns as they’re known in Wales – are those magical high lakes that appear as you’re sweating your way to the top of the mountain. The Rhinog Range in Snowdonia has more of them per square mile than anywhere else in Wales. Swimming in them provides a total landscape immersion and an ultimate sense of the wild. Llyn Eiddew has a shallow side with grassy sheep-mown banks for picnics, perfect for wading in. There’s also a deep side with cliff ledges for sun lounging and jumping in. A backdrop of bracken and stone peaks completes the scene.
2. Granchester meadows, Cambridgeshire
Take tea in Grantchester, Cambridgeshire, and enjoy a length of the River Cam that has changed little since Edwardian times. It was here that Rupert Brooke, Virginia Woolfe and other creative minds gathered to camp, picnic and swim naked. On a hot summer day, the languid mile-long stretch of river is still dotted with dons drinking Pimm’s. Punts and canoes glide by, some heading downstream towards Cambridge’s famous Backs, others upstream to the delightful Orchard Tea Gardens. Anywhere along the meadows is good for swimming, particularly on the outside of the bends where the river deepens, often to more than 1.8m (6ft).
3. River Avon, Claverton weir
4. Waterfall Woods in the Breacon Beacons
The River Ouse, which winds through the Sussex Downs, is one of the most beautiful waterways in the south-east. Its grassy banks are a perfect place for swimming races, leapfrog and other riverside hijinx. You can picnic at Barcombe Mills in open meadows or head upstream to the remote riverside Anchor Inn. Here you can hire one of its fleet of blue paddle boats and row or swim for more than two miles through remote and beautiful countryside. The spire of Isfield church is the only building in sight for the whole journey.
6. Plunge pools in the Cheviouts
On the edge of the Cheviots, the legendary Linhope Spout is a high shoot that falls into a perfectly round plunge pool, renowned for its unfathomable depth. Popular with walkers and families needing to cool off in the summer, there is a 1.8m (6ft) ledge from which you can jump, though the most daring climb ever higher. Many stand for hours trying to summon up the courage, but you should make your decision to jump long before you climb up. Complete a thorough reconnaissance beforehand, checking water depth and obstructions, then clear your mind and step out!
7. Underwater Arches in Skye's faerie pools
The Faerie Pools on the Isle of Skye lie serenely in a sheltered glade of red-berried rowans and lilac rock. The misty towers of the Black Cullin kingdom rise above like great Gaudi spires, the remnants of a huge volcano. Some of the pools are tinged with pinks and greens, and two are linked by an underwater arch. If you swim underneath, you’ll see the rock face is encrusted with pieces of quartz, and there is an almost phosperescent emerald glow. In scenery as magical as this it’s not difficult to imagine faeries and nymphs.
8 Water babies in the River Dart
The River Dart, in Dartmoor National Park, Devon, is the setting for Charles Kingsley’s The Water Babies. And with its sandy bays, oak gorges and deep pools, this is one of the most beautiful wild swimming rivers in the UK. Several miles up a twisted path from Newbridge, in the forest halfway to Dartmeet, you can lie on flat hot rocks by a gurgling river and feel a world away from civilisation. Dense woodland tumbles down the side of the moor, a light spray lifts off the water and the forest murmurs with birdsong. This is a place made for lazy picnics and a swim on sunny afternoons.
9. Lake district mountain views
The Esk is a delightful mountain stream that tumbles down from England’s highest mountain peak: Scafell Pike. There are deeper pools all along its course and you can dip in them as you climb the mountain, making this a spectacular aquatic walk on a hot day. Tongue Pot is the most beautiful, and the perfect place for lunch. Just beneath a packhorse bridge in a rocky cleft, about an hour’s walk from the road, this long emerald pool has formed beneath a waterfall at the meeting of two rivers. A white pebble beach shelves down on one side and an oak tree overhangs.
10. Wilderness in the Mourne mountains
Lough Shannagh, County Down, is a wide open loch surrounded by the beautiful Mourne Mountains, but little visited. Half an hour’s walk from the road brings you to its bank, by which point you should be hot enough to want a dip. The lake is framed by several peaks, including Slieve Doan and Slieve Loughshannagh, and the landscape is blanketed with heather and gorse with the odd speckle of marsh cotton. The water is crystal blue and refreshingly cold, but if you’re feeling timid there is a stretch of sand on which to picnic, and from where you can dip your toe in.
Image: Getty, Thomas Barwick
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