Caroline Wilson had longed to visit Mingulay, where her grandmother was born just over a century ago - shortly before the island was abandoned by the last of its people.

When she finally got the chance to make that hazardous journey she discovered a hauntingly beautiful landscape ... and a village that is being steadily buried by sand

Heel y'ho boys, let her go, boys

Bring her head round into the weather

Heel y'ho boys, let her go boys

Sailing homeward to Mingulay!

From The Mingulay Boat Song

by Hugh S Roberton

'ARE you happy to go on?" asks our captain, Donald Macleod, looking at each passenger in turn for an answer. "We may not be able to land." I nod enthusiastically, trying to catch his eye and the others murmur a yes. The captain doesn't look too sure but turns back to the helm and his boat, James Boy, continues to rise and fall on the Atlantic, ever closer to our destination.

We are travelling to Mingulay, an island that is inaccessible for most of the year, an enticement to most who make the hour-long voyage. Climbers, lured by the third-highest sea cliffs in the UK, adventurous wild campers or those, like me, who have a more personal connection.

My late, maternal grandmother, Kate Agnes Maclean, was among the last babies born on Mingulay before the last of its Gaelic-speaking people made a final voyage across the water just over 100 years ago to forge new lives on Barra, Vatersay and the mainland. A population ground down by the inevitable force of progress and the promise of an easier life.

My grandmother died when I was two, sadly, so I have no memory of her. I wonder sometimes what has been passed to me of her character. She was gentle and easy-going, according to my mother Ishbel. She was also a hard worker - a legacy perhaps of her early life on a remote island.

Jonathan Grant, a ranger engaged by the National Trust to monitor the island and its wildlife, looks across at the swell of the waves lashing the neighbouring isle of Pabbay. He has travelled to Mingulay, the most westerly of the outer Hebrides, in worse conditions, he says; but not much.

The boat begins to turn inward for our approach, dinghy bobbing behind. Donald turns off the engine and Francis Gillies, his second in command, steadies us on to the smaller boat that is swirling in the waves. Even now, yards from the island, it is not certain that we will be able to land. A group of seals have surfaced to watch, heads stretched up comically before they disappear with a splash.

We draw into the black rocks, and out again, carried high by the surf, several times. Suddenly Donald breaks into Gaelic. I catch only one word, "Suas", which means "up". There is a loud "Go!" and Jonathan leaps on to the slippery black rocks, the rest of us following. We've made it and there are only the rain-lashed rocks to negotiate on hands and knees.

Donald Macleod has been taking tourists to Mingulay for 12 years but has 60 years experience sailing to the island to tend the sheep that grazed there until around 2000. His family owned shares in Mingulay, Pabbay and Bernaray, before the islands were sold to the National Trust. He takes around 700-800 visitors a year on the 12-mile trip south from Castlebay. The more accessible St Kilda can see 100 people a day in peak season.

Jonathan describes his work here as "the best job in the world". A "site of special scientific interest", Mingulay is home to around 105 different species of bird including puffins, kitewakes and razorbills, as well as a seal population that can fill the entire bay at times. It is also Jonathan's task to keep a close eye on the fragile stone ruins of the village, where my grandmother lived with her five siblings and parents Michael and Flora for the first years of her life.

Born on September 9, 1906 in the family's croft house, Kate Agnes was three when the family left for Uidh, the peninsula on the island of Vatersay - now joined to Barra with a causeway - and had little memory of her first home. However, she talked often of the island, according to my mother, sharing the mixed feelings of most families about their departure. It was a hard existence and while most were happy to go, there was sadness in leaving the security of a tight-knit community, bonded by mutual adversity and small triumphs over the land and sea.

Jonathan leads us to the village and my granny's croft. In 1907, a year after my granny's birth, there were around 30 families (a population of about 135), living in the village. Her father, my great-grandfather, Michael, was known as Am Beanachan, which means blessing or blessed.

Michael, a fisherman, and Flora were both born on the island and married on April 4 in 1894 in Barra. By the time of the 1911 census, when they moved to Uidh in Vatersay, they had seven children. Flora, the last, was born there.

It is hard to imagine two adults and a family of six living in the croft house, now almost completely buried in sand and machair, but Jonathan helps me rebuild it in my mind. Some of the house would have consisted of a simple dwelling byre, the family living at the high end of the cottage, the cattle at the lower (most families had two or three cows).

The earliest settlers are thought to have arrived on Mingulay some 2000 years ago, and the population peaked at around 160 in the 1880s. They had access to a school and latterly, a church, built in 1898 along with lodgings where the priest stayed when he visited the island.

In 100 years' time, the village may have been completely buried by sand and vegetation. Jonathan and a team of volunteers do what they can to preserve the houses but it's a fine balance to preserve without destroying habitat for existing wildlife, he says.

What was it like for Mingulay's community, living a life that had changed little since Medieval time? Childbirth was risky, due to a lack of medical care; winters would have been harsh.

However, there was much to be envied about their lifestyle, according to Jonathan. "They had pretty much all they needed," he says. "They had the sea, for fish, the seabirds, reasonably good agricultural ground. They had a relatively stable population. Compare that to living in a tenement in Glasgow with diseases like typhoid."

School log books, published recently for the first time online, show that children enjoyed a high standard of education under the tutorage of school master John Finlayson, from Lochcarrron, who remained on Mingulay until his death in 1904. Pupils were described as "bright, willing and wonderfully intelligent" in official reports.

When the men who became known as the Vatersay Raiders took their case for crofting rights to London's Old Bailey, a case that drew support from across the UK, court officials were surprised that they could write in English, Gaelic and Latin.

People on Mingulay also escaped the worst of the Clearances that ravaged Barra and Vatersay. After the forced sale of Barra in 1838 by General Roderick MacNeil, it was bought by Colonel John Gordon of Cluny in Aberdeenshire. The worst Clearances came in 1851 when many were forced to move to Canada, where they arrived in utter destitution.

While islanders on Mingulay had remained in possession of their land for the simple reason that it was not good enough to be taken from them, the island was now overpopulated with the evacuees from elsewhere in Barra. Towards the end of the century a series of factors contributed to a decline in morale and a growing awareness for the need for a change in the way of life.

"Life just became more awkward," says Jonathan. "The men could be gone for days fishing and the women were left behind. At the time the herring industry in Barra was the largest market in Europe. Fisherman understandably wanted a share.

"The priest could only come once a month," he adds. "That was one of the deciding factors. The priest was a very important person in their lives and they weren't getting access. The church didn't want a congregation that wasn't under their direct control."

The lack of a pier not only made fishing difficult but also put problems in the way of easy access by a doctor in an emergency.

My granny's family left around 1909 and most of the community had abandoned the island by 1911 when notice was served by landowner Lady Gordon Cathcart, who wished to let the island along with Pabbay and Bernaray to a grazing tenant.

A succession of owners followed before a sizeable donation from American Jane Fossett allowed the National Trust to buy Pabbay, Mingulay and Bernary on behalf of the nation in 2000.

My granny left Vatersay at 16 to find work as a chambermaid in Oban, later settling in Lochaber to raise a family. Her sister Flora moved to Glasgow and the others stayed close to their roots on Vatersay.

Their brother Donald, a sailor in the merchant navy, boarded a boat and left the island as a young man and the family never heard from him again. They don't know if he died at sea or jumped ship for a new life in America. It was of great sadness to my great-grandmother, my mother says, that she died at 88, never knowing his fate.

Jonathan urges me to come back to Mingulay, with more time and a tent, to get a real sense of the island.

"It's a special place," he says. "A place you can't see in a couple of hours. There's nothing better than sitting on the hill above the village on a summer's evening. You can capture an essence of things that happened in the past."

Jonathan leaves me for a moment, alone at my granny's house, the silence broken only by the relentless surge of the waves. I consider that she would have heard the same sound every day, as would generations before her, and the distance between us shrinks.

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