The 2012 sailing facilities have been unveiled in Dorset, making it the first Olympic venue to be ready for the Games.
The Olympic and Paralympic sailing events will be hosted at the Weymouth and Portland National Sailing Academy, which boasts some of the best small boat sailing conditions in the world.
Early completion of the £6.5m project means that champions from the Beijing Games such as Weymouth-based sailors Sarah Ayton and Paul Goodison can train on home waters and use the facilities ahead of 2012.
Gold medallist Mr Goodison was amongst those invited to see the completed site in Portland, along with former triple jump champion Jonathan Edwards, who is part of the London 2012 Organising Committee (LOCOG).
Other guests included Ralph Luck, director of the Olympic Delivery Authority (ODA), Edward Leask, chairman of the sailing academy and Jim Knight, MP for South Dorset.
Contractors Dean and Dyball started in March to enhance the existing sailing facilities with a permanent 250m slipway and race-boat parking, lifting and mooring facilities.
The work involved demolishing existing marine structures and buildings abandoned by the Royal Navy when its Air Station closed in 1999.
About 80,000 tonnes of Portland stone was used to reclaim 18,000m2 of land in front of the sailing academy to form the new slipway, with a new steel framed academy building.
There is a 200m breakwater to protect the facilities and a pier featuring two yacht-lifting cranes and a pontoon with 70 berths for race-boats.
Dean and Reddyhoff, developers for the South West Regional Development Agency (SWRDA), is also creating a new 600-berth commercial marina at Osprey Quay on Portland, 250 of those berths will be used during the 2012 Games.