Video report by ITV News Anglia's Stuart Leithes
A cancer survivor in his 80s from St Neots is taking on the London Marathon in memory of his wife who died of the disease.
Pete Alsop, 82, will be 83 by the time the marathon comes around on April 28.
Mr Alsop, who survived prostate cancer after being diagnosed with the disease in 1997, will power walk the 26 miles as a tribute to his late wife Val who died from bowel cancer.
He is also hoping to raise money for Cancer Research UK as a thank you for everything they have done for him and his family.
"My Val died from cancer 11 years ago and I had cancer as well," Mr Alsop told ITV News Anglia.
"Through cancer research, the drugs that I took helped to give me three years of clear health and it's my way of thanking them by doing the London Marathon and raising money."
In preparation for the challenge, Mr Alsop has been pounding the streets of St Neots three times a week, doing as much as 15 miles at a time.
It's thought that Mr Alsop will be the oldest person to participate in the London Marathon on behalf of the Cancer Research UK.
"I have no doubt that I can do the distance," he said.
"I'm just looking forward to doing it. The bit that I'm more frightened of is getting there and making sure I'm there on time!
"But the event itself, I'm really looking forward to."