Broadcaster Jonathan Dimbleby is taking on an endurance challenge this summer in celebration of the charity founded in honour of his father, Richard, who died 50 years ago this year.
As chair of the charity, Jonathan is leading Dimbleby Cancer Care's 50/50/50 event on Friday 5 June – a 50km walk through London during the night that aims to raise £50,000.
Dimbleby Cancer Care was set up in 1966 in memory of broadcaster Richard Dimbleby and is based at Guy's and St Thomas' hospitals.
It gives practical and psychological support to people living with cancer and to their families and carers.
Jonathan said: "This year kick starts our charity's 50th anniversary. We want to mark the occasion with a great event that also raises lots of money.
"I've never walked around London at night. It's a long way but I am really looking forward to it – though I haven't spoken to my feet about it yet!
"We are starting at St Thomas' which is where my father spent his last days. His only complaint was the pillows were too hard.
"This was the stimulus that made us decide to make a contribution to the needs of people living with cancer.
"I hope that lots of sympathisers will join me to raise the kind of money needed to sustain this work and boost our 'Care for the Future' appeal."
Starting in the evening, the walk's route takes in famous London landmarks including Trafalgar Square, Buckingham Palace, the British Museum, the Tower of London, Canary Wharf and Greenwich.
The walk is sponsored by Leon, the healthy fast food chain co-founded by Henry Dimbleby, son of David Dimbleby.
Participants can register as individuals or in groups to take part in the event.
All the money raised will go towards the charity's 'Care for the Future' appeal, which aims to raise £500,000 over the next two years so that it can continue and expand its work within the cancer community.
To sponsor Jonathan Dimbleby, visit www.justgiving.com/Jonathan-Dimbleby-50-50-50/
To take part in the event or for more information, visit www.dimblebycancercare.org/50-50-50 – booking closes on 5 May.