The first 2012 Olympic sporting venue to be completed has been unveiled on the West's 'gold medal coast'… on time and to budget.

The completion of the £6.5 million addition to the Weymouth and Portland National Sailing Academy was described by Sebastian Coe, chairman of the 2012 Organising Committee as a catalyst for the region.

It is also a huge morale boost for Weymouth which is holding its breath to see if a £150m makeover for its theatre, ferry terminal and harbour area will go ahead in the credit crunch.

Beijing gold medal-winning sailors Sarah Ayton and Paul Goodison already train in the waters off Weymouth and Portland, which boast some of the best sailing conditions in the world.

They will be looking to defend their medals there before tens of thousands of spectators. The early completion of the project will give them and the rest of the community, including thousands of schoolchildren, the best possible sporting facilities, and the region a major sporting legacy.

Goodison, a gold medallist in the laser class in Beijing, was among 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.

Other guests included Ralph Luck, director of the Olympic Delivery Authority, Edward Leask, chairman of the sailing academy and Jim Knight MP for South Dorset.

Mr Coe said: "We have to put athletes at the heart of the 2012 Games and the facilities at Weymouth and Portland will provide competitors from all lover the world the best possible arena for medal-winning performances.

"Completing our construction works for the first venue for 2012 is a huge milestone and delivers an early legacy of world-class facilities for Weymouth and Portland for sailors of all ages and abilities to use well ahead of 2012. Delivering the first venue on time and to budget keeps us firmly on track as work accelerates on this unprecedented project."

Goodison said: "Winning gold in Qingdao was an amazing experience. I am now looking forward to 2012, training and competing out of the Weymouth and Portland National Sailing Academy on my home waters." Ayton, who married her fiance and fellow Olympic sailing squad member Nick Dempsey in Weymouth in October, won gold in the yngling class with crew members Pippa Wilson and Sarah Webb. Bryony Shaw, who won bronze in the RS:X class also trains in the same waters.

Contractors Dean and Dyball started in March to enhance the sailing facilities with a permanent 250m slipway and race-boat parking, lifting and mooring facilities.

The work involved demolishing 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 18,000sq m 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, developer for the South West Regional Development Agency (SWRDA), is also creating a new £4m, 600-berth commercial marina at Osprey Quay on Portland, 250 of those berths will be used during the 2012 Games.

The marina will include shops and industrial development with the aim of bringing social and economic regeneration to the area. It will have 560 annual berths with up to 40 extra berths for visitors and is due to open next year, with 300 berths initially ready by April.

The SWRDA acquired Osprey Quay after the navy air station closed in 1999 and is regenerating the 33-hectare site. Since the closure of the navy base a commercial port has been re-established.

Borough councillor Howard Legg said "The completion of the improvement works at the Weymouth and Portland National Sailing Academy well ahead of the Games and within budget now provides us with world-class facilities.

"This will not only assist with the training of our national sailing team and help maintain their profile as the best in the world, but provide lasting beneficial benefit to the local community, as we have already seen with thousands of Dorset children already having used the facilities through the Sail for a Fiver scheme".

Portland's first four-star hotel, a £10m building, took its first guests this week as the tourist industry prepares for the invasions to come.