A group of four men are set to run 240 miles in just two days in memory of an endurance athlete who died tragically aged 30.
The group are beginning their challenge in Wimbledon Common and running the length of England to Fylde, Lancashire.
Ben Trend was holidaying with his wife in South Africa in 2010 when he drowned in a freak accident.
The quartet, who include Ben’s brother Jeavon Trend have been training for 18 months and practicing running through the night.
The marathon will last 48 hours and the men will run non-stop in pairs in order to raise money for four sports groups or individuals.
Jeavon, who lives in Wimbledon, called it "the challenge of a lifetime."
He said: "Ben was a passionate runner and an accomplished endurance athlete. He ran marathons all over Europe and tackled some of the toughest events in the world, including the 151-mile Marathon des Sables and the 100-mile Mont Blanc Ultra Marathon."
Ben Trend Get Involved Foundation helps set up physical challenges and sports events to raise money for charity.
It also provides funding and support to individuals and organisations involved in sport in South West London and Blackpool and Fylde.
Sarah Clark, a close friend of the men, said: "I’m so excited for the boys. I’ll be with them from the start and lots of people will be running alongside them for parts of the marathon. We’re calling ourselves the Dream Team supporters.
"The boys will burn more than 25,000 calories, it’s an amazing challenge."
So far the group have raised more than £6000 for their four causes.
Mr Trend said: "We are hoping this event will raise £10,000 in total which will benefit many sportspeople in the regions where we live who lack crucial funding."
To donate visit www.justgiving.com/TheBenTrendUltra2013
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