The aquatics centre's wave shaped roof, the most difficult engineering job at Olympic Park, has been lowered into place.

The £300m building is being built by Balfour Beatty, and the lowering of the roof culminates a seven month engineering project.

The 2,800 tonne roof tops the Zaha Hadid designed venue, which is being named the 'Gateway into the Games'.

The roof has been carefully designed to stretch, contract and twist in response to different weather conditions and changing temperatures.

Work will now begin on the aluminium roof covering and installation of the timber cladded ceiling will begin early 2010.