Around the same time she died, he was visiting family in Northamptonshire.
While there, a friend of the family was also diagnosed with lung cancer.
"It came to me almost as a vision, to do a walk for Cancer Research," Moore said.
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"It was really hard, but it was in my mind to do something bigger than that ... so I walked the whole of the country from end to end."
His first walk in New Zealand was in 2002, where he walked from Cape Reinga to Bluff in aid of the Cancer Society.
This time, however, he was walking in aid of Melanoma NZ, and in memory of family friend Jim Denam, who died three years ago aged 94.
He came over to New Zealand as a member of the "Barmy Army", the supporters of the English cricket team.
Since the cricket was being held in Mount Maunganui, and his plane landed in Auckland, he figured he might as well take the time to walk for charity as well.
Moore said he chose Melanoma NZ because he felt that people in New Zealand didn't respect the sun enough. He was unsure how much he had raised.
He wanted to support a charity which was bringing awareness to the dangers of skin cancer, he said.
"I've been on tour many times and you see sunburned fans all the time," he said.
"You might get away with that in Africa, the sun is different there ..." But here, it's very bright and harsh.
He said it was a case of walking up to people and telling them to put sunscreen on, even if it was darker outside.
The highlight of Moore's walking, he said, was Kaikoura, but he enjoyed walking the South Island in general because it was so scenic.
"All of the South Island I've enjoyed ... you're on the coast a lot of the time," he said.
"Innumerable highlights ... that's why I've written a book."
He's actually written three books, each one highlighting a different part of his New Zealand travels.
He said anyone who wanted to do the long walks for charity had to bear in mind the danger of road walking.
"Do it, but be mindful it's very dangerous out there ... particularly with truckers," he said.
"If you're out there walking they won't give you any consideration, they'll just hope you can jump out of the way... be mindful of what you're letting yourself in for."
Moore's next stop is the Hamilton test match.