Jari Cennat Tammi Swims 500km From Stockholm to Helsinki For Longest Unsupported Swim WR

It takes approximately an hour to fly from Stockholm to Helsinki. For 64-year-old Swedish adventurer Jari Cennet Tammi, travel time was considerably longer.

courtesy of Jari Cennat Tammi

This month, Tammi completed his 500 kilometer swim from Stockholm to Helsinki, setting a world record for longest unsupported swim. He reached Helsinki on August 2nd, meaning that it took him a total of 52 days to make the trek.

That time includes “4 days moving slowly to the last island on the Swedish side, and 10 days waiting for the right conditions for the 33.3km long crossing,” Cennat told SwimSwam.

The right conditions he was waiting for had mainly to do with the wind. Last year, he attempted this same swim but was forced to abandon after 180km. A change in wind direction caused him to miss the island of Lågskärfyr, a 1500-meter long strip of land that was the only landing spot for 50km. With that experience in mind, Cennat told Outdoor Swimmer before his race that he would “only swim this section of the route when there’s a westerly wind to keep him on track for the island.”

He towed a kayak carrying his food and gear the whole way. At the start of his swim, the kayak weighed 105kg.

During his swim, he actually set a second world record. His 33.3km crossing of the Ålands sea–the crossing he waited so long to do–marked a new record for longest unsupported swim on open water.

The world record for longest unsupported swim was previously held by Jonas Deichmann. In 2020, Deichmann swam 450km on the first leg of his triathalon around the world.

Tammi tracked his swim on his Garmin. He also updated his Facebook page every day during the swim. There, he detailed everything from his camp sites and meals to the temperature of the water. This last was a

regularly, sharing the distance he’d covered each day as well as his estimated arrival times in Helsinki. You can take a look at both for an in-depth look at what the swim was like, as Tammi documented everything from his camp sites and meals to the temperature of the water. This last was a major factor in Tammi’s swim, as he reported in his last update that he found out in some parts of the swim it was “only 7 or 8 degrees [celsius].”

His final day was a 21.8km effort to the finish to avoid the bad weather of the next day. He was greeted at his finish line of the Allas Sea Pool on the Helsinki waterfront by his family.