Close to the tourist centre of Pokhara, Lake Begnas has many advantages for the first-time, open-water swimmer.

BBC: Long-distance swimming in Nepal��s glacial mountain lakes

Dale Oen's death comes 18 months after American open-water swimmer Fran Crippen died during a race in the United Arab Emirates, also at the age of 26.

CNN: World champion swimmer Dale Oen dies suddenly

Although training in a pool is an essential part of an open-water swimmer's regimen, it doesn't prepare one for the kinks of swims longer than 10 miles, or at temperatures below 60 degrees.

WSJ: Brighton Beach: Brookyln's Swimming Mecca