William Trubridge swims through the Arch at the Blue Hole in Dahab (an infamous spot, deadly for scuba divers) with no fins, no suit, and just one breath of air.
It’s 60m (196 feet) down and 30m (98 feet) across. Insane. Pure and simple. (But also very awesome).
And here’s Natalia Molchanova doing the same thing – beautifully – with a monofin.