@Daniel564 I swam competitively for 15 years through college and I've done a 10 mile open water swim before so I feel pretty confident saying it would be incredibly painful to swim 25 miles. When I was in my very best shape and swimming 25 hours a week I think I could have done it, but now just a few years out I know there's no chance in hell I would come close. The world record time for the mile swim in a pool, which is much less physically taxing, is around 14 and a half minutes so even at WR pace you're looking at at least 5.5 hours of straight swimming. Ain't gonna happen.