On a beautiful but nippy day in the middle of February, the journalist and broadcaster Kirsty Wark has sailed to the island of Arran to visit the places that inspired her first novel, and up on a hill on the east of the island, in a corner of an isolated cemetery, something unexpected has happened.

In the novel, Wark's main character, a doughty Scotswoman called Elizabeth Pringle, volunteers to search for survivors after a plane crash and as Elizabeth climbs the hills with the other volunteers, she starts to see Arran in a different light. "Who could have foreseen that the magnificent peaks of Goatfell, and her jagged, ragged crags, would be transformed into a death trap for so many?" she says.

The character of Elizabeth Pringle is the work of Wark's imagination but the plane crash isn't - it really happened. On August 10, 1941, 22 passengers and crew took off from Prestwick en route for Canada. As the plane flew over Mullach Buidhe, north of Goatfell, Arran's highest peak, it hit low, dense cloud and crashed, killing everyone on board.

Wark, who is 59, read about the crash when she began to write her novel, The Legacy Of Elizabeth Pringle, and incorporated it into the story, but what she didn't know - until today - is that many of those who died in the tragedy are buried on the island. The graves are in Lamlash, on the island's east coast, and during our visit we find them, unexpectedly, while wandering round the cemetery.

It is a moving experience for Wark and, as she walks along the line of headstones, she reads out some of the names: Captain HCW Smith (Canada); Captain JE Price (Australia); Captain WM King (Texas). "They are so far from home," she says. And then she comes across the names of two women: Private Anne McNabb and Private Flora McNabb, who died later in an unrelated incident in 1944. "What's going on there?" she says. "I want to know about this. I want to know their story. I want to write about them now."

This curiosity about the isle of Arran, and a desire to tell the story, is pretty much how Wark's novel got started, although it is also partly inspired by her family history too. When Wark was a little girl, she would come from Glasgow to Arran on holiday and she still comes here with her children. There are nuggets of this family history in the pages of her novel and we are here on the island today to winkle them out.

We start with her great-uncle James Wark. In the novel, Elizabeth's father writes from the Western Front during the First World War. Peace has just been declared but he has something else on his mind. "The only thing I worry about," he writes, "is that the flu might get over the sea to Arran."

He is referring to the great Spanish influenza pandemic which killed millions of people in 1918, but the tragedy in the novel is that, even as he is fretting about his family, it is he who has become infected with the flu and, just a few days after the Armistice, he dies of it.

Like the crash on Goatfell, this story is based on truth - it happened to Wark's great-uncle James. "James volunteered early on in the war," says Wark. "He was from Glasgow and joined one of the pals' battalions, but served with the 47th Battalion Machine Gun Corps, and served right through the war as a gunner."

Later, after we return from Arran and are back at Wark's home in Glasgow, she shows me the letters James wrote from France. The first one is dated November 13, 1918, and in it he talks about the four years of misery he's been through. "The only thing I worry about is the flu doesn't get round Jordanhill way," he says. Four days later, he writes again, telling the family he is "in the pink". On the 21st, he was taken ill and on the 29th, he died.

Wark was given James's letters by her mother and keeps them in a little box at home along with pictures and other mementos. "I love old things that connect me with previous generations of my family," she says as she leafs through them. "And you get a strong sense of James's personality through the letters - he was a gentle person but also very determined."

Also in the box is a picture of Wark's father, who inspired another of the characters in the novel: Mr Hardie, the lawyer who handles Elizabeth's will, which mysteriously passes her house on to a woman she never knew. In the book, Mr Hardie is the classic, old-fashioned Scottish lawyer and Wark says that is pretty much what her father James was like.

One of the earliest memories of him, she

says, is on one of those family holidays on Arran. As we walk along Brodick beach, she tells me she remembers playing here with her dad. She also remembers riding along on the back of her dad's bicycle along the Shore Road and that memory is in the novel: she "would squeal with delight and pummel her father's back as he zigzagged one way, then the other, throwing her from side to side".

It's a happy memory for Wark, although she says she and her father didn't talk much about large parts of his life and they certainly didn't talk about what he did during the Second World War. She knows he was badly wounded in the D-Day landings and worked as a counter-intelligence officer in Germany but that's about it. "I always wonder if he went back to work as a counter-intelligence officer because he was only in battle, as it were, for three days," she says. "We never talked much about it."

They also never talked much about his health - something else which is explored in the novel when Elizabeth falls ill but hides it from everyone around her. Her friends can hear her hacking cough in the bathroom and everyone knows she is seriously ill, but she refuses to face up to what is happening.

Wark says that is based on what happened to her father when he started to show the symptoms of lung cancer. "The hacking cough in the bathroom - that was him," she says. "And the denial. My dad did that. But I heard the cough. So I knew."

He did give up smoking, she says, but it too late. "It's only now I'm realising," she says, "one of my characters in the novel, Susie, displays anger at her father for smoking and I probably have that at my dad. He smoked until the last couple of years and if he'd stopped sooner, he might have lived longer, although there are no guarantees.

"Also, why didn't I force Dad to talk about his time in Germany? He wouldn't talk about what he did but I think it gave him a stoicism; it gave him an interior life - seeing friends killed in June 1944 never really left him - he was a young lieutenant leading a platoon and he saw men killed."

She stops and thinks a bit more. "It's the reason I wanted to write about the war: we're now approaching a generation that will not know about those kind of deaths. That's not true if you have family in Afghanistan or Iraq, but in that broader sense, we will never know what it was like for people."

Wark's father eventually died of cancer in 1993, but the death of her mother, Roberta, is more recent. Although in many ways Elizabeth is an archetypal elderly Scottish woman, there are elements of Roberta in the character too. In fact, The Legacy of Elizabeth Pringle is essentially about the relationship between mother and daughter and what it feels like when one of them dies.

"My mother wasn't particularly demonstrative or emotional," says Wark. "And I was closer to my dad emotionally, but I learned a lot from her about the practical things in life." Wark's mother loved tapestry for instance (a skill she passed on to her daughter) and also liked to save money by reusing, recycling and collecting, which is something else Wark has inherited.

As we walk along the beach, for example, Wark keeps a close eye on the sand for little treasures. She picks up a fragment of a plate and holds it up to the light like it's precious. "Look at that," she says. "Isn't it beautiful?"

Further along the beach, she explains more about some of the subtle connections between the story of Elizabeth and the story of her mother in real life; the book is essentially truth and fiction intertwined, she says, and was partly inspired by losing both her parents.

"Mum's death was more recent," she says, "It was only four years ago, from pneumonia, overnight, and it was ridiculously badly handled by the ambulance that came for her. I think it was her home help who called to say 'Your mum is unwell, and the ambulance has been' and I said 'What? Been?' and I went shooting down to Kilmarnock and she couldn't breathe very well. If she'd been taken in by the ambulance, I think she would have had more chance of survival."

Wark explores this territory in the novel: what it feels like for a daughter to deal with the frailty of their parents, and their mortality. "I always remember the writer James Runcie saying you don't really grow up until your parents are dead," she says. "I'm not sure that's true for me, but I do think there was a passing of the baton on to the new generation. One feels older."

We've reached the end of the beach at Brodick so we jump back into the car and drive along Shore Road with Holy Isle on the horizon to our left. In the novel, Wark writes about how the great liner Queen Mary did her speed trials in this stretch of water in 1936 and that too has a real-life family connection: Wark's grandfather on her mum's side was an engineer at John Brown's shipyard.

There are many other moments from the

history of Arran in the book. There's Winnie Drinkwater, for instance, who flew sorties over Arran and made aviation history in 1930 by becoming the youngest aircraft pilot in the world when she was 17. There's also Rev Robert Kirk, a Church of Scotland minister who wrote about a world of fairies which he believed was real. And there's the story of how the two world wars affected Arran: the children who were evacuated there and the men who left the island to fight and never came back.

And there's one other piece of history in the novel that is also connected to Wark's story. In the book, Elizabeth Pringle is faced with a difficult decision: should she leave Arran with her fiance to start a new life in New Zealand or should she stay on the island that she adores? In the end, the pull of the land is too much for her and she decides to stay and that dilemma was inspired by another of Wark's relatives: her great aunt Berta.

"Berta was engaged to be married to a boy in Lanarkshire," says Wark, "and at the last minute she said she couldn't go to Australia because she couldn't leave everything behind - she couldn't leave her family, she couldn't leave the beautiful house."

Wark says she understands that. She may live in Glasgow and work in London when she's presenting Newsnight, but coming to Arran so often has given her a connection to the land and its history. She points up to the white peaks of Goatfell as she explains what she means. That's a view that's remained unchanged for hundreds of years, she says.

"And I love that," she says. "If I didn't come here often, I'd feel the lack of it. I'd feel bereft. I could never leave Scotland and it's family and friends, but it's the sense of place too and that's particularly powerful for Scots. It matters. It matters a lot." n

The Legacy Of Elizabeth Pringle by Kirsty Wark is published by Two Road Books on March 13, priced £14.99.