Photograph by David Clifford

"Deepwater soloing provides the perfect combination of adventure and serenity," says Jessa Younker of climbing the stalactites hanging from a giant limestone cliff on Poda Island, Thailand. "Without a rope or harness to distract, I can purely focus on how to make the next move on the natural features." With this style of rock climbing, a fall is followed by a splash: "Sometimes my hand would slip off the wet rock and send me free falling through the air. Then I would be engulfed in the warmth of the Andaman Sea, swimming towards the surface, watching the sun dance across the gentle waves."