I slipped in over the smooth rocks and was soon surrounded by ocean, pushing myself along slowly with my rusty front crawl. The sandy floor sank away and seaweed swayed with the tide underneath me. I tried to think what I’d call the plankton-speckled, bluey-green water in the lexicon of paint colours: Greenland Moss meets Tahitian lagoon, perhaps?

Swimming in the sea close to England’s most westerly point felt revitalising. And not just because of any lingering grogginess from the overnight sleeper train from Paddington, nor even the sheer joy of my first escape from London in eight months. After a year in which I avoided Covid but discovered and was treated for cancer, it was simply an affirmation of still being alive. Seagulls squawked overhead and sweet-tasting salt water sloshed around my mouth.

I’d arrived earlier that day to stay at the Carbis Bay Hotel near St Ives, which will host the G7 summit next month. According to a government spokeswoman the location was chosen because “Cornwall’s stunning landscape, as well as its culture of innovation and sustainability, provides a perfect setting for world leaders to come together and discuss how to respond to global challenges like coronavirus and climate change.”

The hotel was built in 1894 and has now expanded to 125 acres, with 38 rooms in the original building as well as “Valley” apartments tucked in behind and sumptuous tri-level beach lodges with rooftop hot tubs that face the waves and wouldn’t seem out of place in southern California. There are several restaurants and a spa where perhaps Boris and Joe might bond over a mani-pedi. Virginia Woolf stayed here for three weeks in 1914; To The Lighthouse was inspired by Godrevy Lighthouse, on the far side of the bay.

On my visit, the site was a flurry of expectant activity, with building work for G7 meeting rooms going on apace — something that has not gone down well with local residents and environmental groups who’ve staged occasional protests. Multiple delivery trucks pirouetted in the small car park, hikers trod around them on the South West Coast Path, and hotel workers scurried about delivering breakfast hampers.

Meetings over, the world leaders won’t find much to occupy them in the village of Carbis Bay itself. The highlight is undoubtedly the magnificent beach, with the hotel at its centre, reached down a steep road that will undoubtedly be cut off by the army of security that will descend in June. The wide bay itself has clear waters that hide several shipwrecks; some of them vessels that were bringing Welsh coal for the steam engines in Cornish tin mines.

Map of Cornwall

The much more characterful town of St Ives is a half-hour walk away along a coastal path, past more elaborate, recently constructed homes with lots of glass and pointy angles, one of which had a “G7 — put climate first” sign fixed on its gate. En route, before you drop down to Porthminster beach, you’ll pass a black and white lookout, The Baulking House, from the 1800s, where a watch was kept for shoals of pilchards in the bay so boats could be directed towards them.

The main catch now is tourists, a batch of whom sat bundled up against a northerly wind on the deck of the Porthminster Beach Café. I chatted to the Australian owner, Mick Smith, about the ups and downs of last year. His main concern wasn’t so much getting back to “normal” life — inside dining is allowed again from Monday — as the problem of attracting workers who can’t afford to live in the area. “Last year was challenging and stressful,” he told me over a flat white, “but even when we’re expecting a bumper summer this year, we struggle to find any staff . . . everyone that works in hospitality is priced out of the local housing market.”

St Ives certainly seemed to be coming back to life after Covid, with plenty of families parked on benches looking out over the harbour, guarding ice creams, chips and Cornish pasties from beady eyed seagulls. Pretty white houses contrasted glaringly against the cloudless blue sky and on Porthmeor beach, overlooked by the Tate gallery, lifeguards’ flags flapped furiously in the biting wind.

The main purpose of my short break in Cornwall was to swim along the coast with local guide Tom Foreman, who, with his business partner Jo Brown, offers “seafaris”, navigating several kilometres each morning and afternoon over three days. Although he offers location-specific trips too, such as around St Michael’s Mount (currently off-limits due to the shooting of a Game of Thrones prequel), there’s an element of daily surprise based on what the wind and tides are doing.

I’d planned to swim at Carbis Bay, perhaps to offer some guidance for world leaders to follow in my wake, but the buffeting northerly wind there meant my first dip with Tom was actually at tranquil Penberth Cove, five miles or so as the chough flies south-east of Land’s End, England’s most westerly point. Apart from a man attending to his fishing boat and a family sitting on the rocks eating doughnuts, we had the place to ourselves.

“Considering Cornwall’s got more than 400 miles of coastline”, Tom told me as we got changed, “I’m always surprised how many tourists see the sea as just something to look at. I’ve always wanted to be in it.” Swimming with him, there’s a sense of exploring, rather than simply cooling off. “And because we’re a peninsula, I can pretty much always find somewhere calm to swim. If the wind’s coming from the north, we’ll just head south.”

I poured myself into my wetsuit, which offered good protection from the 11C water — later in the season it can get up to 19C — but my hands and feet stung for the first few minutes, and my face tingled. We stuck close to the rocky shoreline, following it round, doing a loop back on ourselves to the starting point about 45 minutes later.

I felt very safe with Tom, who seems to personify the laid-back Cornish lifestyle that many incomers aspire to. He first began swimming in the sea at the age of 14 and spent many years as a lifeguard in both Cornwall and Australia. When it was just the two of us, he swam alongside with a float bag, but for larger groups he uses a paddle board that anyone can hang on to if they need a rest. He also offers coaching — I needed to keep my head up and bum down, and to get my elbows higher on each stroke, so he advised I try to brush my armpits with my thumbs as my arm came over my head.

The next day the wind was still coming from the north, so we drove to the Lizard peninsula, joined by a couple of Tom’s friends from St Agnes, one of whom was practising to swim the English Channel. We parked up at the small village of Cadgwith and wandered through the lanes of pretty houses, down to the harbour where tractors pull fishing boats up from the beach. After rounding the small headland, we swam along the black cliffs and through an archway to a tiny cove known as the Devil’s Frying Pan, due to the hiss of the sea smacking against the rocks in storms.

Lunch was a Cornish pasty at Kynance Cove, where the high tide hid the golden beaches that draw huge crowds in summer. We drove onwards and slipped back into the water at Coverack, with the seawall and former lifeboat ramp on our right, rounding the headland where the sea was calm. I swam for about an hour before heading back, refreshed and pleasantly tired, sharing flapjacks and cake in the car park as we dried off.

On my final morning, I drew back the curtains hoping to see millpond conditions at Carbis Bay, but the northerly was still blowing. Although I couldn’t swim there, I did go out in a canoe with Jo and some of his mates, before they ran me over for a final dip with Tom at Mousehole, a fishing village that was sacked by the Spaniards in 1595. I did a few sheltered laps within the harbour walls, dodging lines of fishing boats while two other swimmers headed out to St Clement’s Isle, 200 metres offshore.

The G7 leaders may not have time to put on their cozzies and splash around off the Cornish coast next month, but I’d highly recommend it. The world might be a calmer place if its leaders bobbed around on their backs for a while, switched off, emptied their minds, gazed up at clouds and just connected to the sea. It worked for me.

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