Outside the back door of Philip and Avril Copithorne's farmhouse sits a huge cast-iron cauldron - lichen-spattered and brimming with rainwater. Called a famine pot, it's a memento from those terrible years when a potato blight ruined the harvests of Ireland's staple crop (easy to cultivate in poor soil; tasty and filling mashed up with a little buttermilk) and millions starved or fled, mostly to America in packed "coffin ships". The pots were used to make a thin, maize-based gruel called stirabout. This one has been here since the Great Famine ended in 1851, which means, as Avril points out, "It would have been here when your people were here." But who are my people, and why am I here at Fort Arthur, an isolated farm near the village of Ballinspittle in south-west Ireland? It all started when, back home in London, an Indian friend, confident in her ethnicity, was teasing me about my daughters' names: "Scarlett and Molly O'Connell!" She chuckled derisively. "Those aren't children - they're Irish theme pubs." Stung, I protested that I was Irish, sort of. But she wasn't having any of it: "You've never even been to Ireland," she said. This was true and, I had to admit, pretty shameful. I could plead only laziness and a woolly-liberal belief that who you are is more important than where you come from - an easy enough piety to rehearse if you're lucky enough for it always to have been the case. Actually, though, if we're going to play this game, I'm Irish on both sides. My great-great-grandmother on my mother's side, Mary Hanagan, was born in Rathangan in County Kildare in 1833. But I find the O'Connell connection more alluring, not just because I have inherited the name, but because it feels more obscure and mysterious. That said, as surnames go, O'Connell is humdrum to the point of utter drabness - the Irish equivalent of Smith. A favourite genealogical pursuit for O'Connells is trying to establish links to the most celebrated O'Connell of all: Daniel the Liberator (1775-1847), who campaigned for the right of Catholics to sit in the British Parliament and whose statue stands at one end of the Dublin street named for him. I have no such ambition. I just want to find the house where my grandfather - christened, like me, John Patrick O'Connell - was born in 1868 to a farmer, Thomas, and his wife, Catherine. It's been tricky to uncover many concrete details about his life, not least because he died in 1938 when my father was nine; and his second wife, Marjorie, my grandmother, died in 2004, aged 102. She rarely spoke about John, or Jack as she called him. She was 23 when they married; he was pushing 60. Jack had known her since she was a child: he was her family's doctor while Marjorie was growing up in Seven Kings in Essex. My father has no memory of Jack ever discussing his parents or childhood. As a couple, Jack and Marjorie travelled all over Europe - their favourite holiday was hiking in the Swiss Alps - but not once did Jack suggest they visit Ireland. Perhaps this upright, middle-class professional was ashamed of his peasant origins? It's interesting to speculate. In the early 19th century, most Irish Catholics were attached to the land as tenants at will or agricultural labourers. Living conditions were harsh and the mortality rate high. Large families were the norm, with the joys of children (and creating children) being among the few permitted within the confines of their religious mores. Yet John Patrick O'Connell was an only child - perhaps because Thomas died shortly after he was born when he fell off a horse and broke his neck. Historians have noted that those who survived the Great Famine benefited from its legacy, and it's likely the O'Connells of Fort Arthur were one such family. The harvests of the 1850s and 1860s were mostly good. Mass emigration shrunk the population so that by 1900 it stood at just 4.5 million. Farms expanded, becoming more efficient and profitable. But above all it must have been the education reforms lobbied for by the Irish National Association (founded in 1864) that enabled this poor Catholic farmer's son from the rural south-west to study medicine in Dublin and reinvent himself as the cultured, cosmopolitan man my grandmother married. Before she died, my grandmother confided in my aunt the name of Jack's birthplace, Fort Arthur; also that it was close to the upscale resort town of Kinsale, where I've based myself. I know that Fort Arthur still exists and that it used to be a rare breeds farm. But a bit of light research suggests it isn't any more. It looks as if it might now be a boarding kennels. I ask the receptionist at my hotel - the pleasant, boutiquey Blue Haven on Pearse Street - for directions and she taps the name into Google Earth. "There it is," she says, pointing to a geometric, pastel-hued house amid a raggedy patchwork of deep-green fields. "It'll be hard to find. Your best bet is to stop at the shop at the crossroads before you turn off to Ballinspittle and ask there." I'm so hopeless at navigating, I can't even find the shop. So I drive on a bit further and see two farmers - at least I think they're farmers - mucking about with a tractor. I wind down my window and ask if they know where Fort Arthur is. They do, and they tell me. But I can see suspicion in their eyes - suspicion of my clothes and English accent. One of them asks: "Are you a harrier man?" It takes a few moments for my brain to unscramble the dialect; a few more to work out what he means. And then it dawns on me: this is hunting country, and Philip Copithorne, who currently farms at Fort Arthur, is master of the local hunt. "No," I say, feeling rather too much like Withnail [in the UK film <i>Withnail and I</i>]. "I'm not a harrier man." Outside Ballinspittle, I pass the famous grotto where, in the mid-1980s, a statue of the Virgin Mary was alleged by some teenagers to have moved. Moving-statue mania ensued as half of Ireland descended on the area. Today, the site is well tended, with fresh flowers and newly painted railings. But the viewing benches on the bank opposite are empty. As for Mary, she's as static as you'd expect. Fortunately for me, Fort Arthur Boarding Kennels is signposted. I turn off the main road onto a bumpy, unmade track. My stomach dips as the house approaches. So this is it - the place where, to paraphrase Philip Larkin, my grandfather's childhood was unspent. Will the Copithornes be in? And will they be friendly? Yes, and yes. Philip answers the door. Avril makes us tea. As we sip, she explains that they keep sheep, cattle and horses as well as dogs. She also shows me her collection of garden gnomes - the largest I've ever seen. Sadly, the old farmhouse where Jack was born was knocked down 15 years ago. "It was derelict for ages," remembers Avril. "The roof was falling in and there was a drainage ditch running underneath it. Philip's people took it over in the 1920s and he remembers staying there. I don't think it was much fun." The house had a broader historical significance, she says. The Irish patriot leader Arthur O'Connor, who secured help from the French for the 1798 rebellion he'd helped to foment, hid out there from British troops. It's bitterly cold, but the sun remains bright. Avril lends me boots and we walk across the frozen, churned-up mud towards the ancient ringfort that gives the farm its name. Even though it's set decades later, in the 1930s, I'm reminded of Patrick Kavanagh's novel of rural Irish life Tarry Flynn, a charged account of a bachelor farmer's relationships with work, women and nature: "He stooped down under the belly of the animal to catch the girth strap and as he did he caught a glimpse of the morning sun coming down the valley; it glinted on the swamp and the sedge and flowers caught a meaning for him. That was his meaning." I may not be manhandling a horse, but for a moment it's my meaning too. Next, I head to Holy Trinity Church in Ballinspittle where I've been told the Parish Records are stored. I'm keen to find out if my great-grandparents were married here; presumably Jack would have been baptised here too. But the parish priest, Father Kelleher, is 81 and not in a position to help. "There's no-one in the church to attend to you," he says. "All the records are in the National Library in Dublin." Which is all well and good - except I'm not in Dublin. I am, it suddenly occurs to me, about 8km from the Old Head of Kinsale, Ireland's most dramatic headland. I decide that I've done enough family history research for one day and head off to take in some scenery. The view is as spectacular as everyone says. In the distance I can see navy warships - perhaps on manoeuvre, perhaps guarding against overfishing. In May 1915, a German submarine torpedoed the passenger liner Lusitania here as it was sailing to New York, precipitating America's involvement in the First World War. The inquest into the sinking was held at the triple-gabled courthouse in the centre of Kinsale that currently does duty as a museum. Being ghoulish, I'm excited about seeing the actual deckchair from the wreck that my guidebook assures me is on display. I estimate that, if I hurry, I can fit in a visit to the museum before lunch - but unfortunately it's closed. (Much of Kinsale is closed when I visit in early March: the tourist season doesn't start officially until St Patrick's Day on March 17.) Less than half an hour's drive from Cork Airport, Kinsale is a pretty place - a stately, well-kept town on the edge of a harbour, the yachts in the marina sedately bobbing tributes to its prosperity. Once it was a key trading post, but nowadays it's mostly famous for its gastronomic excellence - for restaurants like the Fishy Fishy cafe (where I drain a bowl of steaming chowder in a matter of seconds), The Vintage, Crackpots and Blu at the Blue Haven hotel. It's a comfortable, modern resort and a great base for exploring the scattering of bays and estuary towns along the south-west coast - places like Skibereen and Clonakilty, the birthplace of Republican leader Michael Collins. On my final morning I drive 10km to Bandon, where my great-grandmother, Catherine, is supposed to have opened a shop after Thomas's death. On the way back to Kinsale I stop for a quick Coke at The Spaniard inn, perched high above the town. People are friendly and open. Everyone asks who I am and what I'm doing. And, I notice, not for the first time, the way they relax when I tell them my surname. I'm not sure how I feel about that, and I wouldn't say I came to County Cork looking for a sense of belonging. But it feels as if I've found one anyway.