Celebrating the launch of Swimathon 2010, the world's biggest fundraising swim, a team of swimmers from Greenwich Leisure (GLL) joined a host of celebrities and GB elite female swimmers in the pool at Crystal Palace National Sports Centre, operated by GLL in partnership with the London Development Agency (LDA) .

At the launch, four of Britain's fastest female swimmers - Olympic silver medallist Keri-Anne Payne, Jessica Thielmann, Sophie Casson and Danielle Hall-Jackson - set the fastest official female 5km team time in Swimathon's 23-year history.

The new mark is now exactly 58 minutes.

Also swimming in the 50m pool were celebrity supporters Zoe Salmon and Swimathon President and Olympic gold medallist, Duncan Goodhew along with the GLL team.

More than 20,000 people have signed up for Swimathon 2010 and all are out to beat last year's fundraising total of £1.5m.

The fundraising will help support Marie Curie Nurses, providing free nursing care to cancer patients and those with other terminal illnesses in a place of their choice.

This year's event also saw the launch of the 'Swimathon Hall of Fame' with awards presented to the highest fundraiser ever; the fastest male and female ever in each age category and participants who have entered every Swimathon since it began.