Canoe Slalom: Campbell Walsh gives Olympic slalom course a test run

The Scot said: "The course looks great. I am sure it will make a spectacle of a race for the Olympic Games."

Glasgow-born Walsh, 33, who is hoping to better the silver he won at the 2004 Athens Olympics, said it was "hugely exciting" to test the rapids at the new 31 million Lee Valley White Water Centre.

He was speaking as the Hertfordshire venue, the first purpose-built 2012 venue completed by the Olympic Delivery Authority (ODA), was unveiled by the Princess Royal.

Walsh, the 2008 European Champion, was joined by other members of Britain's canoe team who have been set a target of winning three medals at London 2012, two of which are expected to be gold.

It will be a major training and competition venue, but members of the public will also be able to raft and canoe there from April 2011. The key course features two drops and a straight run of continuous white water, good for competition.

John Armitt, chair of the ODA which began work in July 2009, said: "Seeing canoeists and rafters use the courses for the first time gives us a glimpse of the excitement we can expect here in 2012 and the world-class new facilities that people of all ages and abilities will be able to use for many years to come."

London 2012 chair Lord Coe noted the site is a "world-class venue that would not have been built without Britain staging the Games".

He said: "With the centre open to the public both before and after the thrilling action at Games-time, it really does demonstrate the great legacy that London 2012 will leave for users, from elite athletes to kids from local communities."

The centre is in the heart of the 10,000-acre Lee Valley Regional Park.

Facilities include an Olympic standard 300m competition course, with a boat conveyor to transport participants to the course start in their rafts or canoes and a 160m intermediate/training course.

There is a 2.5-acre finish lake and a pump house building containing a reception, cafe, changing rooms, offices, spectator viewing facilities, storage, water pump and filtration plant.

British Canoe Union chief executive Paul Owen said: "We now have in Britain the best white water stadium in the world and we look forward to providing a sensational event for the 2012 Olympic Games in a venue with a lasting legacy."

Funding has come from Lee Valley Regional Park Authority, the East of England Development Agency and Sport England.

Olympics Minister Hugh Robertson said: "This is now a major competition and training venue for elite athletes while the public rafting and canoeing facilities will bring more new people to the sport and help leave a legacy from hosting the Games."