Ross Edgley has become the first swimmer to complete a circumnavigation of Great Britain – a 1,780-mile (2,864km) trip that took 155 days.
The 33-year-old was joined by 300 fellow swimmers as he made his triumphant return to dry land in Margate.
Mr Edgley had left the Kent town on 1 June and had not set foot on land throughout his challenge, which at times involved swimming for 12 hours a day.
But his feat has not been without difficulties, and the extreme athlete has had to contend with shoulder pain, a chafing wetsuit and even his tongue starting to partially disintegrate because of the seawater.
His odyssey was compared from the outset to the feat of Captain Matthew Webb, who in 1875 became the first person to swim the English Channel.
He entered the Guinness Book of World Records on 14 August, 74 days into the challenge, for the longest staged sea swim, according to the World Open Water Swimming Association.
By that point, Edgley, from Grantham in Lincolnshire, had reached the Isle of Skye.
A growing army of supporters, including more than 117,000 Twitter followers, kept up with his progress via a series of weekly vlogs for sponsors Red Bull.
He has expended an estimated 500,000 calories on his epic adventure, with more than 500 bananas providing a constant source of energy.
The round-Britain swim is the adventurer's third entry in the Guinness Book of World Records.
In February 2016, he did a marathon while pulling a car and two months later completed a rope climb the equivalent height of Mount Everest in 19 hours.
But last year he failed in an attempt to swim the 24.8 miles (40km) between Martinique and St Lucia while pulling a 100lb (45.3kg) tree trunk.
In August, swimmer and environmental campaigner Lewis Pugh became the first person to swim the length of the English Channel, under traditional Channel swimming rules.
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