Czech free-diver David Vencl swam nearly 81 metres (265.75 ft) beneath the ice on Tuesday, breaking the world record after braving the freezing water wearing only a swimsuit.
"This will do," Vencl said after emerging from his minute-and-half swim in water measured at temperatures of 3 degrees Celsius and pumping his fist in celebration.
The 38-year-old changed the location for the record attempt to a former quarry in Lahost, 100 kilometres north-west of Prague, from a glacial lake in Austria due to COVID restrictions which made international travel difficult.
Vencl, who dropped into the water through one hole cut in the one-foot-thick ice before emerging from another, beat the previous record of 250 feet set by Denmark's Stig Avall Severinsen in October, 2017 in southern Greenland.