Hunter Davies bought his Dartmouth Park house for £5,000, and when people move into his road he likes to tell them to "watch their faces drop as they vomit on the floor".

Before that, his first marital home with novelist Margaret Forster was in the Vale of Health, and over six decades the author and journalist has visited the Heath every day, walking, swimming, playing football, and raising three children.

The 85-year-old, who thinks he may be the only living person to have a commemorative bench on the Heath, has written an affectionate book which blends personal anecdote, history and interviews with key players from The Heath and Hampstead Society and City of London Corporation, to swimmers and dog walkers.

"I realised I had been living beside the Heath for 60 years and had all my memories of swimming, my football team, and the changes - the activities that have gone like the Irish builders who used to play Gaelic football on the slopes of Parly. Now you have people playing Quidditch with sticks.

"The book gave me an excuse to visit places I hadn't been to for years like the Pergola, or look more closely at things like the Farmers Market, which I mocked at first as phoney Hampstead people putting on Barbours and wellies to cross the trenches of the Heath and ponce around with organic rubbish. And one of the many perks of being a journalist is getting into places you wouldn't otherwise, like up the backstairs of Kenwood."

Started in June 2019, the book is framed as 'My Year on Hampstead Heath,' but of course "Covid happened and I thought 'bugger this has ruined the whole story', because everything closed, you couldn't swim or go anywhere."

But he says the pandemic offered both peace and narrative drive: "It was a lovely productive time for me, I was in the middle of one book and the Heath was so quiet at the beginning you almost had it to yourself. Then I could reflect the changes as the closed signs went up, how when the weather got better there was four times the normal traffic because people were escaping into the countryside. You can still see the mark of Covid in the tramped down verges and the massive fence beside the men's pond."

Davies, who hails from Cumbria, has donated his £10,000 advance to the Heath and Hampstead Society which is celebrating 150 years since an Act of Parliament protected the Heath for all.

He started working on Fleet Street in 1959, and wrote his first novel in 1965. 100 books later he has penned children's stories, a behind the scenes at Tottenham Hotspur, a year in the life of a Muswell Hill comprehensive, and ghostwritten memoirs with Wayne Rooney and Paul Gascoigne.

But it's his 1968 Beatles biography that brought fame - and hopefully - fortune. As he points out, when the band split in 1970 it was unthinkable they would still be discussed 50 years later.

"The further we get from the Beatles the bigger they become in influence," he observes. "Think how their music has affected other groups, they wrote 100 songs that will last as long as there are people on the planet, you can do a PHD in Beatles lyrics, and there are thousands living on them as lookalike groups. Mine was the first book but there have been hundreds since."

Ham & High: The Beatles rehearsing at the EMI Studios in St John's Wood. Picture: PAThe Beatles rehearsing at the EMI Studios in St John's Wood. Picture: PA (Image: PA Archive/PA Images)

In 1966 he heard Eleanor Rigby, "thought it was brilliant, and interviewed Paul McCartney".

"I pitched a Beatles biography to my publisher as social history, but they said 'we know everything we want to know about The Beatles, the bubble will burst, and books about pop music don't sell.'"

Davies did persuade them - then he had to convince the band.

"By then they were pissed off with being The Beatles, they were still making records but had stopped performing in public and had enough of being the most famous people on the planet. Someone like George I found very hard because he couldn't be bothered talking about The Beatles, he wanted to talk about Indian spirituality."

Davies argued he could correct the many inaccuracies about the band, and: "If I do a proper biography, for the rest of your life, when people ask the same boring questions, you can say 'it's all in the book'."

Then he visited manager Brian Epstein: "My advance was £3,000 we agreed I would give a third to Brian and The Beatles, then out of the blue he said: 'I will put a clause in the contract - no access to The Beatles until two years after your book comes out'. Two years later they didn't exist, so I was the only authorised biographer and got access to all the mums and dads, Aunt Mimi, George Martin, people now long dead. I didn't want to stop. Every album was totally different with new influences, new clothes, I felt I would miss something."

Davies has turned over his 37 research notebooks to the British Library for posterity but says "I can't decipher a bleeding word."

Widowed in 2016, he still writes daily, "in my sleep," has four newspaper columns, including writing on football and late life relationships with new girlfriend Claire. His 102nd book will be on The Isle of Wight where he has a home.

"I keep on saying this book will be my last, but I tend to write about real people and I would miss that."

The Heath: My Year on Hampstead Heath by Hunter Davies is published by Head of Zeus. £25 hardback.

Ham & High: The Heath by Hunter Davies is published by Head of Zeus priced £25The Heath by Hunter Davies is published by Head of Zeus priced £25 (Image: James Oses)