Congratulations to Josef Köberl on completing the Tsugaru Strait!


Swim date: 3rd September 2026

Age: 49

Nationality: Austria

Country of Residence: Austria

Swim Start Time: 03:35

Swim Finish Time: 14:01

Completion Time: 10 hours 25 minutes 44 seconds
Swim Distance: approximately 48km

Swimming Style: Free style

Water Temperature: 23.6℃ – 25.3℃ *Sea Surface Temperature

Air Temperature: 24.6℃ – 25.7℃

Relative Humidity: 77％ – 97％

Wave Height: 0.5m – 1.0m

Wind Speed: 1.3m – 5.0m
Stroke Rate Per 60 seconds: 56 – 63

Swimmer’s comment

Crossing the Tsugaru Strait was one of the most extraordinary experiences of my swimming career. The currents, waves, whirlpools and many jellyfish made this much more than a physical challenge. There were moments when the sea clearly showed me that I could not control it – I could only adapt, trust the captain and the team, and keep swimming.

After 10 hours, 25 minutes and 44 seconds, reaching Hokkaido as the first Austrian to successfully cross the Tsugaru Strait was an incredibly emotional moment. It also marked my sixth Ocean’s Seven crossing.

But I will remember much more than the swim itself. From the moment we arrived in Nakadomari, we experienced extraordinary kindness and hospitality. I felt that the TSSF, the captains, observers and everyone involved genuinely cared about our safety and about making this crossing possible. Waiting for the right weather window was difficult, but it showed me how much experience and responsibility goes into every successful crossing.
I leave northern Japan with enormous respect for the Tsugaru Strait – and with great gratitude to everyone who helped me reach Hokkaido.

Observer’s comment
At the meeting on 29 August, I found Josef to be a very composed person. When checking the escort boat, he discussed key reference points and the ideal route with the captain, which gave me a strong sense of his determination to complete the swim.

After departing Kodomari Port on the day of the swim, he remained focused and calmly made his preparations.

The sea conditions were relatively calm during the first few hours. However, once he entered the strait, the waves grew higher, and there were areas where whirlpools had formed.

Changes in the currents also meant that we had to adjust the intended direction and swimming position several times. At these moments, naturally he became frustrated at the conditions. However, once the direction was settled, he regained his composure and continued swimming.

There were times when Josef had to stop temporarily for safety reasons or struggled to make progress against the currents, which made me concerned about whether he would be able to finish. However, he eventually caught a favourable current and I was absolutely delighted when he successfully completed the crossing.

After completing the swim, he climbed back aboard the boat with confidence and energy, which left a strong impression on me. Congratulations to Josef on completing the Tsugaru Strait crossing!
Observer: Kaito Kumaki