This one may be a little more challenging than the last.
Deep in the forest was found the body of a man who was wearing only swimming trunks, snorkel and facemask. The nearest lake was 8 miles away and the sea was 100 miles away. How had he died?
(side note there are no rivers in this forest, and the streams are much to small to even fill a canteen from.)
edit- Orpz was correct!
Explanation -Spoiler : Answer :