During the pandemic, when Miriam Leitko couldn’t swim because pools were closed, the lifelong swimmer built a lap pool at her home in Willis, Texas. As soon as travel restrictions were lifted in 2021, she signed up for a weeklong trip to Hawaii with SwimVacation, a Maine-based tour operator that specializes in open-water swimming.

“Open-water swimming becomes energizing,” said Ms. Leitko, 64, who has taken 12 trips with the company. The tours, she said, allow her to leave her stress “literally in the ocean.”

Summer vacations are often built around the pleasures of cannonballing into a lake or splashing in the ocean. In contrast, these tours build trips around organized swims that might involve diving among sea lions in the Galápagos, swimming island to island in the Adriatic or gliding over coral reefs in the Caribbean.

“You never feel smaller than when you’re in the ocean, which has a transformative effect,” said Hopper McDonough, the founder and a partner in SwimVacation, which bases most of its trips on yachts in places like Turkey, where the next available departure is September 2024 ($6,995 for one week).

“After the pandemic, we sold out two years in advance,” he said.

Whether participants are seeking transformation, pursuing a Covid-stymied passion or revenge traveling, swim tour operators say they are experiencing a tidal wave of growth.

The England-based company SwimTrek, established in 2003, pegs the explosion to the pandemic-driven outdoor movement.

Nearly a third of SwimTrek’s clients — and growing — are from the United States, where the company has added vacations in Hawaii and Oregon (five days in Oregon’s Cascade Lakes costs $2,600) as well as trips to Canada, Mexico and the Caribbean.

“When you swim in open water, every experience is different, whether that’s the state of the sea, the tides or the wildlife,” said Simon Murie, the founder of SwimTrek. “That’s the beauty, the unpredictability.”

Strel Swimming Adventures, founded by Martin Strel, a marathon swimmer who holds the Guinness World Record for distance swimming at 5,268 kilometers, and his son, Borut, met the surge with new Mexican destinations, including the Sea of Cortez (seven-day trips in October and November from $1,990). The company also offers tours in Greece, Slovenia and Turkey.

Active England, an English adventure operator, has seen “exponential” growth in its swim tours since travel resumed, according to Will Cairns, the company’s founder. Its trips include four days in Devon from June to September for 759 pounds (about $984), with swims in the sea, an estuary and, after a two-mile walk in Dartmoor National Park, a natural pool in the River Dart.

“We have what I call ‘advanced swimmers’ who measure their swims in kilometers,” Mr. Cairns said. “But the majority of people do it for the love of the water.”

Most tour operators divide swimmers into subgroups based on speed and claim to take everyone from former Olympians to occasional dippers interested in swimming two to five kilometers a day (open water swimming is usually expressed in metric terms).

Not all new swim tours are hard core. Bluetits Chill Swimmers, a group devoted to wild swimming — a popular term in Britain for swimming in natural bodies of water — recently partnered with a travel company to offer swimming trips to places like Iceland, where a five-day package includes dips in hot springs, the sea and the fissure at the rift between tectonic plates (the £2,265 fall trip sold out shortly after it was announced this spring).

“Swimming with a group of people who are like-minded and don’t want to marathon swim is a wonderful, joyous occasion,” said Sian Richardson, who founded the group,which celebrates participation rather than competition and now has more than 120,000 members in community groups from Copenhagen to the Great Lakes.

Much Better Adventures offers wild swimming on its multisport tours, which also include hiking and cycling in places like the Canadian Rockies (10 days from $2,103), the Canary Islands (six days from $1,166) and Dominica (nine days from $2,375).

“We don’t believe that all wild swimming needs to be about speed, tow floats or fancy neoprene,” wrote Sam Bruce, the co-founder of Much Better Adventures, in an email. “Instead, just being in the water in a wild place is enough.”

Whatever the difficulty level of the tour, safety is a selling point. Most operators send boats to escort open-water swimmers and choose their locations to avoid dangerous currents, high winds and boat traffic. Trips also go where it may be hard to swim solo.

“Someone else has done the planning for you,” said Kate Rew, the founder of the Outdoor Swimming Society, a British volunteer group that promotes swimming outdoors, who has traveled with SwimTrek. If you’re doing a couple of kilometers in new places, she said, “you need a lot of knowledge and local contacts.”

And there’s at least one side benefit. “People sleep so well,” said Mr. Cairns of Active England. “Two to three swims a day is exhausting.”


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