No one should swim alone and, if possible, always swim under the watchful eye of a certified lifeguard.

CNN: Water safety expert: 'Drowning doesn't just happen'

Adventurous travellers can swim under the waterfall via a natural swimming hole at the bottom of the falls.

BBC: Kauai��s hidden adventures

Visitors can swim under waterfalls or in natural pools, explore miniature caves and dive off a 5m-high wooden platform into the balmy waters below.

BBC: Livin�� la vida Bonito

The sinuous main pool, with a swim-under fountain and swim-up bar, is so massive I had trouble recognizing my friends on the other side of it.

FORBES: Escapes

Dana Vollmer, the first woman in history to swim the 100-meter butterfly in under 56 seconds took Gold at the London Olympics.

FORBES: Dana Vollmer: The Definition of What it Really Means to be a Champion

Crew is well equipped to swim upstream, given its recent turnaround under CEO Mickey Drexler , a veteran from Gap, who took the reins in 2003.

FORBES: Magazine Article

Well, the town of 20, 000 north of Worcester is pretty darned proud of its girls swim team, which won 16 state titles under Lemieux despite training in fairly modest facilities.

FORBES: For Want Of A Swim Trophy, One High School's Winter Sports Teams Banned From Postseason

He said he hoped to complete the 2.4 mile swim, 112 mile bike ride and marathon in under 11 hours in October.

BBC: Herne Bay Ironman student's air ambulance fundraising

The sheer quantity of water gushing under bridges meant the otters could not swim against the rapid current, so they tried to cross the road instead and often got hit by cars.

BBC: New threats to UK otters' survival