There used to be offshore races in water like that here back the '80s and before. I'm pretty sure '85 was the last year Key West ran around Sand Key on a long course on the edge of the reef. It was 10 miles to the first turn. Notice the open boats would run 98 miles, 98 miles and 156 on Saturday. They were true World Championships.
The red shows a typical modern day course. Not sure anyone runs much more then 98 miles in the entire week.
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