The 2012 Olympic sailing venue in Dorset is being used for first time in a major international sailing regatta.
The annual Skandia Sail for Gold Regatta runs until Saturday in Weymouth Bay and Portland Harbour.
The Weymouth and Portland National Sailing Academy (WPNSA) was one of the first UK venues to be ready for the 2012 Olympic Games.
More than 700 competitors in 500 boats will be battling it out in 10 Olympic classes over the next six days.
They include about 100 Skandia Team GBR members who will be competing against their international rivals.
Beijing gold medal winners Paul Goodison, Andrew Simpson, Iain Percy and Pippa Wilson are among those taking part.
Other international names at the regatta include Australia's Beijing 2008 gold medallists Elise Rechichi and Tessa Parkinson.
Stephen Park, Royal Yachting Association (RYA) Olympic manager, said: "In sailing there is no substitute for experience in the venue when it comes to winning medals.
"[This regatta] provides Skandia Team GBR with a fantastic opportunity to line up with the best in the world and gain that all-important knowledge and racing time in the venue where we hope to be successful again when the Games are upon us in less than three years' time."
Hampshire yachtswoman Dee Caffari reviews what Portland has to offer the 2012 Olympics
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