Britain opened the first venue for the 2012 London Olympics on Friday when it unveiled the sailing facilities in southwest England.

The Olympic and Paralympic sailing events will be hosted in Weymouth Bay and Portland Harbour in Dorset, which are regarded as having some of the best sailing conditions for small boats in the world.

The early completion of the 6.5 million pound ($A15.2 million) Weymouth and Portland National Sailing Academy means Britain's Olympic hopefuls can use the venue for training to get an early advantage on their competitors.

Locally-based Sarah Ayton and Paul Goodison, who both won sailing gold medals at this year's Beijing Olympics, attended the opening ceremony along with former Olympic triple jump gold medallist Jonathan Edwards.

Work began in March to enhance the existing facilities by adding a permanent slipway and race-boat parking, as well as improved lifting and mooring facilities.

The work involved demolishing existing marine structures and buildings previously used by the Royal Navy and adding a new steel-framed academy building.

AFP