Devon man becomes first person to swim Switzerland’s 10 largest lakes

Neil Gilson completes 230-mile challenge after a ‘tough’ 22-hour crossing of Lac Léman

He staggered rather than sprang out of the lake but it wasn’t surprising.

Neil Gilson , a former international athlete, could be forgiven for feeling a little wobbly, having become the first person to swim the 10 largest lakes in Switzerland, a total of about 230 miles (370km).

Over the last two summers, Gilson, a father of three from Devon in the English West Country, has ticked the lakes off and on Wednesday he finished swimming the 45-mile length of Lac Léman (Lake Geneva), taking just over 22 hours.

His 12-year-old daughter, Lily, and 10-year-old son, Jack, were in the water waiting as he neared the end to accompany him across the finishing line.

“They swam the last 200m with me,” Gilson said. “There were tears in my goggles. For the whole challenge, I was envisioning that moment. It kept me going through some difficult times – lovely.”

Gilson, 40, was once ranked second in Britain for the 1500-metre freestyle and after finishing race swimming, turned to endurance challenges. In 2024, he swam across Lac Léman in 22 hours and nine minutes, a world record. But it wasn’t enough. He decided to tackle 10 Swiss lakes.

Gilson put in countless hours in the pool at a leisure centre, the sea off the north Devon coast and the gym to prepare.

There have been blips. Gilson admits that a swim of about 40 miles in Lake Maggiore this summer almost broke him. It was colder than he anticipated and he had to swim more quickly to get his core temperature up, which meant he used more energy than planned. He had “nothing left” for the last few miles.

Lake Thun proved surprisingly difficult as the pressure to complete the challenge – and the physical effort – caught up with him. After clambering out of the lake, he said: “My arms don’t like me and I feel shattered.”

Gilson said he found swimming in lakes more demanding than the sea. “They’re more unpredictable. You can get some really choppy conditions because of the wind and you can hit walls of cold water.”

He began Léman on Tuesday morning and finished on Wednesday lunchtime. He admitted that 18 hours into the swim, he thought of giving up. “It was so tough in the night – the current was strong. I felt really close to stopping but what kept me going was my family waiting there.”

Gilson said his support team, which accompanied him in a boat, helped by giving him coffee – and saying “the right things”.

He just missed out on beating his own world record for Léman, but is confident Guinness World Records will recognise him as the first to complete what has been billed the Legend of the Lakes challenge – and in subsequent years, that other ultra-swimmers may try to do it more quickly.

As well as doing the swim as an extraordinary challenge, Gilson is seeking to draw attention to a neuropsychiatric condition, Pandas, that affected his son at 18 months old. People with Pans or Pandas experience a variety of symptoms ranging from mental health symptoms to changes in behaviour and difficulties with movement.

Jack was diagnosed with Pandas after catching tonsillitis. “He went to bed a happy, healthy little boy, and woke up as someone we didn’t recognise, gripped by aggression, OCD [obsessive-compulsive disorder], tics and intense fear; he refused to eat, wouldn’t leave the house or even speak. It was terrifying,” Gilson said.

Jack is doing well – as shown by his joining his dad for the last leg of his swim – but Gilson said: “The challenge has always been about more than swimming. Every lake, every kilometre and every difficult moment has been about raising awareness of Pans and Pandas.

“It’s a condition that isn’t rare but is rarely diagnosed. Raising awareness of it means more than anything.”