Polish ultra-distance swimmer Bartłomiej Kumbkowski has secured a place in open-water swimming history, becoming the first person to swim across the Baltic Sea from Sweden to Poland.

After roughly 55 hours of unbroken effort, without sleep and without touching the support boat even once, he covered more than 160 kilometres, successfully completing his fifth and most demanding attempt.

Kumbkowski set off on Friday from the Swedish coast and reached the beach at Dziwnów, in West Pomerania, Poland, on Sunday evening, shortly before 8pm.

Hundreds of supporters greeted him on the shore, where, in keeping with the challenge’s rules, he had to walk out of the water unaided for the achievement to be officially recognised.

Minutes after finishing, he admitted he was so exhausted that he “still didn’t know” how he felt about having managed to cross the Baltic.

Congratulations to Bartłomiej Kubkowski who just became the first person ever to swim across the Baltic Sea between Sweden and Poland.

He spent 56 hours in the water without sleeping and swam 160 km (100 miles). pic.twitter.com/DjC4RBoWoi

— Visegrád 24 (@visegrad24) August 2, 2026

160 kilometres without sleep or rest

The mission lasted around 56 hours, during which the Polish swimmer did not sleep for a single minute, never stopped to rest, and never touched the support boat that followed him purely for safety reasons.

Marcin Cieślak, a member of the Purely Athletic team, said Kumbkowski swam without stopping, stroke after stroke, for more than two days, while the crew handled navigation, feeding and his safety.

Hallucinations and the battle against exhaustion

The greatest challenge was not just physical strain but the psychological pressure of extreme sleep deprivation.
Cieślak explained that after the second consecutive sleepless night, hallucinations set in, along with moments when the athlete lost touch with reality.

Despite these episodes, months of preparation covering physical conditioning, nutrition and psychological support allowed the team to keep problems to a minimum and bring the swimmer safely to the finish.

POLAK PRZEPŁYNĄŁ BAŁTYK WPŁAW! 🇵🇱🌊
Bartłomiej Kubkowski dokonał rzeczy historycznej. Jako pierwszy człowiek pokonał wpław ponad 160 kilometrów ze Szwecji do Polski. Płynął niemal 55 godzin bez snu i bez dotykania łodzi asekuracyjnej.

To była jego piąta próba. Rok temu zabrakło… pic.twitter.com/9PkfM38mOx

— Pani Prezes 👠 (@PaniNaSzpilkach) August 2, 2026

Five attempts for a historic feat

The success was the result of an effort that began in 2022. On his first attempt, Kumbkowski managed to cover 115 kilometres, and he drew closer to his goal with each subsequent year.

In 2025 he came within a whisker of success, having swum 159 kilometres. However, just 11 kilometres from the Polish coast he lost consciousness and the attempt was called off.

On his fifth attempt, Cieślak said, he drew on all the experience gained in previous years, showing exceptional focus and management of his strength.

🏊Bartłomiej Kubkowski jako pierwszy człowiek w historii przepłynął wpław Bałtyk ze szwedzkiego Kaseberga do polskiego Dziwnowa, pokonując ponad 160 kilometrów w ponad 54 godziny.

To była jego piąta próba pokonania morza – w zeszłym roku musiał zrezygnować zaledwie 11… pic.twitter.com/HcpVwwYWXs

— NA CZASIE (@naczasienews) August 2, 2026

Gruelling preparation and the symbolism behind the effort

Preparing for the challenge involved punishing training, long pool sessions, night swims and intensive mental conditioning to help the athlete withstand the mission’s extreme conditions.

Kumbkowski dedicated his historic achievement to the children and young people supported by the Cancer Fighters foundation, as part of a charity fundraising campaign.

The Pole holds the world record for 24-hour swimming and is the creator of the Ultra Baltic Swim project, through which he set out to complete the Baltic crossing and raise public awareness for the cause he was supporting.