In preparation for my upcoming swim, The Great Chesapeake Bay 4.4 Mile Swim on June 11, I decided I would do my longest training swim yet at Patagonia Lake on Friday, May 12.

Last month, I measured my course with my old Garmin Forerunner 305 inside a swim buoy that I pulled behind me. Starting from the beach at Patagonia Lake, the course is a counter-clockwise loop, which my Garmin measured as around 1 mile. That closely matched the same course plotted on Google Earth shown below. However, another athlete joined us me the swim on Friday and her Garmin (worn on her wrist) measured the same loop course as 1.38 miles. I’d like to believe that, but I’d rather be conservative when it comes to training. In any event, we swam 5 loops of this course, with quick stops for water and gels.

Patagonia Lake State Park, 1 Mile Swim Course Map

Patagonia Lake 1 Mile Swim Course Google Earth Map