Mr Moore began raising funds to thank the “magnificent” NHS staff who helped him with treatment for cancer and a broken hip.
His challenge and fundraising has been praised by a range of famous faces, with England hooker Jamie George saying he had been “truly inspired” and Piers Morgan calling for Mr Moore to be given a knighthood for his efforts.
Speaking about the fundraising efforts, Mr Moore told BBC News: “It seems almost like fairyland to think that we started off at £1,000 to a sum of money that’s not believable, is it?”
Mr Moore, who recently had a hip operation, is ahead of schedule with his walking, finished the first leg of his challenge today.
Mr Moore, who trained as a civil engineer before enlisting in the army for the Second World War, rising to captain, told the BBC: “I never imagined anything like this, but I’m so pleased, and I hope it just goes on because the services I got from all these doctors and nurses was absolutely outstanding.
“And they’re such nice people too.”
He went on to say;
“Thanks each and every one of you – we are in awe of you, but especially our frontline staff who need this now more than ever.”
Mr Moore, originally from Keighley in Yorkshire, was aiming to walk 100 lengths of his Bedfordshire garden before he turns 100 on April 30.
He hoped to walk 100 laps of the 25-metre (82ft) loop in his garden in Marston Moretaine, in 10-lap chunks.
Mr Moore also told the BBC: “I do [laps] each day, so that eventually I’ll get to 100, then after that I shall continue and do some more.”
He added the support he had received so far had been “absolutely fabulous”.
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