The 450t cable-net roof of the Olympic Stadium has been put in place on the site using 56 hydraulic jacks, marking the completion of a four-week long exercise.
The stadium is the flagship venue for London 2012 Olympic and Paralympic Games.
Over 900t of scaffolding and 1km of support platforms are used to assemble 12,000m of cables and the walkways of the net, which is between the outer steel roof truss and an inner tension ring, 30m above the field of play.
In spring 2010, the roof will be clad with material covering two-thirds of spectators while offering correct conditions for play.
The lighting towers will be lifted into place early next year, enabling the stadium to reach its full height.