The athletics track at the London 2012 Olympic stadium has been completed.
The track is made of synthetic rubber and has been designed to help athletes run fast times. Five world records were set on a similar surface in Beijing.
London 2012 chairman Lord Coe said: "Today marks a huge milestone for the project as the stadium comes to life."
Long jumper Chris Tomlinson, 1,500m runner Hannah England and Paralympic discus thrower Dan Greaves were the first athletes to test out the track.
They were joined on the new surface by local schoolchildren, who will benefit from the Stadium's legacy plan to be a venue for sport, athletics, community and cultural events.
The 80,000-capacity stadium is nearing completion with the latest anticipated final cost of the work being £486m.
The stadium will host the opening and closing ceremonies of both the Olympic and Paralympic Games, as well as all the track and field events.
An 80m sprint straight made of the same material as the main track has been laid under one of the main stands and a 400m training track will be laid shortly.
The track will be covered to protect it from the elements while other work continues at the Stadium.
"People can get a glimpse of how it will look in less than 10 months' time when we welcome the world's athletes to London," Coe added.
"There is still a lot of work to do on the stadium but seeing some of our top British athletes on the track with local schoolchildren really underlines the stadium's potential for 2012 and beyond."
Hugh Robertson, Minister for Sport and the Olympics, said: "This is another piece in the jigsaw for our Olympic Stadium."
Olympic Delivery Authority chairman John Armitt added: "Watching athletes and children run around the Olympic Stadium's track 10 months before the London 2012 Games highlights just how much has been achieved over the last four years."