Canoe slalom gold medallists Etienne Stott and Tim Baillie are making an appearance at the Lee Valley White Water Centre.
The centre is the first London 2012 venue to open to the public after the Games.
Plans have been unveiled for a £4.5 million development of the centre starting in January 2013.
More top news
A 7-metre high sculpture has been installed in the shadow of the Gherkin building, as part of this year's Sculpture in the City exhibition.
Police are looking for a man who sexually assaulted a 12-year-old girl at a London train station yesterday while she was with her family.
A gang of robbers who dressed in burkas to stage raids on high-end stores in London have been convicted today.