After 20 hours and 56 minutes of non-stop swimming, Simon Holliday hauls himself up the steps of Disneyland pier, knees almost buckling, to claim a world first.

The British marathon swimmer has just survived rough seas, testing tides and cramp to become the first person to circumnavigate Hong Kong's largest island of Lantau, a distance of over 65 kilometres (40 miles).

Closely following the 46-year-old is the American Edie Hu, who is all smiles as she takes her first tentative steps on dry land after her own odyssey lasting 21 hours and 28 minutes.

"I started getting a little loopy," the 50-year-old Hu told AFP. "I saw Yoda in the mountains."

The pair started their adventure at 2:00 pm on Thursday, the day before, with a third swimmer in the pod, Brett Kruse.

They were accompanied by

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