Congratulations to Gráinne Moss on completing the Tsugaru Strait!

Gráinne has proudly become the FIRST IRISH WOMAN to achieve the Oceans Seven!!!

Swim date: 19th June 2026

Age: 56

Nationality: Ireland

Country of Residence: New Zealand

Swim Start Time: 04:07

Swim Finish Time: 16:36

Completion Time: 12 hours 29 minutes 15 seconds

Swim Distance: approximately 44km

Swimming Style: Free style

Water Temperature: 16.0℃ – 19.5℃ *Sea Surface Temperature

Air Temperature: 17.7℃ – 26.5℃

Relative Humidity: 57％ – 92％

Wave Height: 0.1m – 0.5m

Wind Speed: 0m – 6m

Stroke Rate Per 60 seconds: 58 – 67

Swimmer’s comment

Swimming the Tsugaru Strait was a truly unforgettable experience. The conditions demanded real respect, and the constantly shifting currents made it a physical and mental challenge right to the very end. From Captain Sato, the observers, administration team and everyone behind the scenes, I always felt supported, even when things got tough.

My time in northern Japan was also very special. It’s a place with a quiet, understated beauty and a deep connection to the water. My family, friends and I felt genuinely welcomed by the community — we only had to look slightly lost and someone would come to help us.

Completing the crossing was the final chapter of my Ocean Seven journey, and I feel very lucky that it happened here, with this team and in this place. The welcome after the swim was unforgettable. That warmth and kindness will stay with us just as much as the swim itself.

Observer’s comment

On the day of the swim, Gráinne appeared calm from the moment we set off, and I felt that they were preparing for the crossing in a composed and focused manner.

Throughout the swim, the waves remained relatively calm, but the current was strong and became increasingly powerful as we approached Hokkaido. There were moments when I felt concerned myself, but Gráinne remained calm throughout and maintained a steady pace all the way to the finish.

When they returned to the boat after successfully completing the crossing, they looked much more energetic than I had expected, which was a great relief to see.

As an observer, I am truly delighted that I was able to witness them overcome the challenging currents and successfully complete the crossing.

Gráinne, congratulations on successfully completing the Tsugaru Strait crossing and achieving the Oceans Seven!

Observer: Shinnosuke Satō