London: Ross Edgley dodged cargo ships, jellyfish and sharks to become the first ever swimmer to circumnavigate Great Britain in a 2,882-kilometre feat that took five months.
Edgley set off from the port of Margate on June 1, swimming clockwise, and finished back in the same spot on Sunday.
"So many people told me it couldn't be done," Edgley said upon arrival, his sponsors Red Bull said in a statement late Sunday.
"Having done it now, what would be amazing is to see people shift their own personal barometer on what they think is possible".
The challenge was documented in video blogs and Edgley was accompanied by Cornish sailor Matthew Knight on a catamaran.
Edgley swam for up to 12 hours a day, battling strong tides and currents in cold water and storms. He suffered shoulder pain, wetsuit chafing and salt water exposure during the swim.
In his first week at sea, Edgley crossed the Strait of Dover -- one of the busiest shipping channels in the world.
After 20 days at sea, he said jellyfish began attacking his face and he started wearing a mask to protect himself.
When he reached Scotland in August, a basking shark swam alongside him.
Red Bull said the 33-year-old had broken four world records.
The first was in July when he became the first person to swim along the entire south coast of England and the second occurred in August for the longest staged sea swim.
He smashed another record by becoming the fastest person on the planet to swim from Land's End in southwest England to John O'Groats in the far north of Scotland.
His fourth record was on Sunday when he completed the challenge.