Bill “Ciastko” Welzien (USA, 75, MSF bio here) completed his 150th warm-water 20.1 km circumnavigation swims around Key West in southern Florida over the last 34 years.

It is thought that Welzien’s 7 hour 16 minute Sesquicentennial Swim is an unprecedented feat for a swim of at least 20 km in the annals of open water swimming.

He reported, “Today’s swim was my ninth swim in the past 18 weeks. 85% of this swim was like swimming in a wash machine. This was swum on a full moon and the tidal assistance was minimal. It was a hard slog.

I thank my two support kayakers, my eldest son  David Welzien and my brother in Christ, David Ezmirly. They were outstanding, especially in the choppy conditions. I thank my precious wife Denise who was there on the beach to greet me. Most of all I thank my Lord and Savior, Jesus Christ for providing me with the perseverance and tenacity in not only on completing this swim, but the previous 149 laps around the Island of Key West. I am thankful for the health I have at 75 years old.”

This week, he finished in 6 hours 48 minutes 45 seconds [see his swim data here].

He explained, “I started in 1991. So it took me 34 years to get to this point. Interestingly, it took me 24 years to get to #65, the year I turned 65 years. Then in the last 10 years since 2005, I have swum 84 completed swims around Key West. My swim #100 (Century Swim) was on May 19th 2018, averaging 6 hours 15 minutes over the first 100 swims.

That means I swam 49 swims in the past 7 years. This year, I have swum the full distance 8 times in 16 weeks. Since February 13th, I have swum the course every other week. I swam #142 on February 13th and #149 on May 28th.”

His sesquicentennial swim is recorded here.

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