'I surfed the largest wave ever ridden' - Garrett McNamara
12 May 2012 Last updated at 16:31 BST
Report first broadcast 12 May 2012
Surfer Garrett McNamara has been recognised by Guinness World Records for surfing the largest wave ever ridden, a towering 78ft (24m) wall of water he says he caught at Nazare, Portugal, in November 2011.
The feat was verified by Guinness after an independent panel of big wave and photography experts measured still and video images of the colossal wave.
The 44-year-old from Hawaii has also picked up a $15,000 prize.
The BBC's Andy Moore reports.