Courtesy of WOWSA, Huntington Beach, California.

Dr. Mark Smitherman, whose nickname is Magoo, is a 57-year-old American marathon swimmer and member of the Half Century Club from Clearwater, Florida.

Today, with a steady 12 hour 32 minute crossing of the English Channel, the internist achieved both the Triple Crown of Open Water Swimming and the Grand Slam of Open Water Swimming.

He completed the Manhattan Island Marathon Swim in 8 hours 10 minutes and crossed the Catalina Channel in 11 hours 52 minutes both in 2014.

He also competed in the 2012 24-mile Tampa Bay Marathon Swim that was cancelled due to thunderstorms, but he came back a year later and finished fourth in the 2013 Tampa Bay Marathon Swim.

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