The trap door lay hidden in the floor of Frederick Bourne’s tower office, a dark rectangle set into the stone that most visitors would never notice. It opened onto a dungeon, an actual dungeon built into the foundation of the castle, cold and silent and unmistakably medieval. Why it was built, no one knows for certain. Some said it was simply part of the architect’s commitment to recreating a fictional palace in every detail.

Others whispered darker theories, that it stored contraband during Prohibition or served purposes the family never publicly acknowledged. The dungeon kept its secrets. The castle itself rose from the dark water of the St. Lawrence River on an island called Dark, so named by early navigators who saw its high granite peak covered with giant pine trees, a dark silhouette against the sky.

It had stone towers with red tiled roofs, a clock tower crowned the whole, and Westminster chimes rang out every fifteen minutes, their sound carrying across the water. Local folklore claimed the clock faces were made of solid gold. They were not, but the legend persisted, adding to the mystique. This was Singer Castle, and its story began not on a romantic island but in a modest home in Boston, Massachusetts, on December 20, 1851, when Frederick Gilbert Bourne was born into a family of preachers and patriots.

His father, Reverend George Washington Bourne, was a man of God. His mother, Harriet Gilbert Bourne, came from Portland, Maine, and raised her children with the stern values of New England propriety. When Frederick was around nine years old, the family moved to New York City, and in the crowds and chaos of America’s fastest-growing city, young Frederick discovered a hunger, not for gold like the thousands rushing west to California, but for knowledge and opportunity. By age eleven he was singing in the choir at Holy Trinity Church, described as having a voracious thirst for knowledge, spending every spare moment reading about mechanical work, history, science, and adventure.

When his father died in 1872, leaving his mother widowed and his younger sisters without support, Frederick was forced to make a choice that would define the rest of his life. He was only fourteen years old. He left school and went to work. His first job was with the Atlantic Submarine Wrecking Company, a rough-and-tumble operation that salvaged ships and cargo from the depths.

He moved through positions, cashier, bookkeeper, clerk at the Mercantile Library of New York, saving every penny to support his mother and sisters. All the while, he kept learning. Frederick loved music, and when he joined the Mendelssohn Glee Club, a prestigious musical society in New York, he was simply following his passion. He had no idea the decision would change the entire trajectory of his life.

It was there, among the harmonies and sheet music, that he met Alfred Corning Clark. Alfred was the son of Edward Kitt Clark, one of the wealthiest men in America, who alongside the inventor Isaac Merritt Singer had co-founded the Singer Sewing Machine Company. Frederick and Alfred became friends, one a working-class clerk supporting his widowed mother, the other the heir to a manufacturing fortune. Alfred saw something in Frederick that others might have missed: intelligence, integrity, ambition tempered with humility, work ethic paired with vision.

In 1880, Alfred recommended to his father that Frederick be brought into the family’s real estate business and made construction manager of a revolutionary new apartment building being built on Manhattan’s Upper West Side overlooking Central Park. The building was called the Dakota. Frederick threw himself into the work, managing hundreds of workers, coordinating with architects, solving problems on the fly. And as he worked, Alfred frequently asked him to attend Singer Sewing Machine Company board meetings in his place.

When Edward Clark died in 1882, Frederick was appointed manager of the Clark estate at age thirty-one. Three years later he was made secretary of the Singer Manufacturing Company, and in 1889, at the young age of thirty-eight, Frederick Gilbert Bourne became its fifth president. The boy who had started with nothing now controlled one of the world’s first truly multinational corporations. Between 1889 and 1905, under his leadership, Singer became what historians now call perhaps the first modern multinational industrial enterprise of any nationality.

He pioneered the installment plan, allowing ordinary families to buy sewing machines through small payments over time, turning the machines from luxury items into household necessities. He expanded Singer’s global footprint, establishing factories and sales offices on every continent. He vertically integrated the company, controlling every step of production from raw materials to final sale. He commissioned the architect Ernest Flagg to design the Singer Building in Manhattan, which when completed in 1908 was the tallest building in the world.

By the time Frederick retired as president in 1905, he had accumulated a personal fortune estimated at forty-two to forty-three million dollars, the equivalent of well over a billion dollars in today’s currency. He maintained an apartment at the Dakota that occupied the entire first floor. He owned a two-thousand-acre estate called Indian Neck Hall in Oakdale, Long Island, next door to William Kissam Vanderbilt’s Idle Hour. He owned a 375-acre hunting preserve near Montauk.

He had an apartment on Jekyll Island, Georgia, home of the famous Millionaires Club. And then, in 1902, he bought a small rocky island in the Thousand Islands region of the St. Lawrence River. It was called Dark Island.

Frederick did not set out to build just a hunting lodge. He turned to his friend Ernest Flagg, the same man who had designed Indian Neck Hall and would later design the Singer Building. Flagg was a graduate of the École des Beaux-Arts in Paris and had developed what he called a modern French Renaissance style. But for Dark Island, Flagg needed a story.

In 1902, his wife happened to be reading him Woodstock, a historical novel by Sir Walter Scott, published in 1826. Scott’s novel told the tale of Woodstock Palace in Oxfordshire, England, a mysterious castle built as a hunting lodge for royalty, filled with secret passageways, hidden tunnels, underground labyrinths, and even a dungeon. As Flagg listened to his wife read night after night, the vision formed in his mind. He would bring Scott’s fictional palace to life, here on a rocky island in upstate New York.

Frederick didn’t want to copy any existing castle. He wanted something original, something that had never existed before. So Flagg took Scott’s literary descriptions and transformed them into architectural reality, creating what would eventually be called the Castle of Mysteries. Construction on what Bourne called the Towers began in the spring of 1903.

Over one hundred masons were employed year-round, working through bitter winters and sweltering summers. The rose granite that formed the castle’s bones was quarried from nearby Oak Island, the same quarry that supplied stone for Boldt Castle, another Thousand Islands mansion being completed at almost the same time. Sandstone came from quarries in Hammond. Red roof tiles were imported all the way from Spain.

Italian craftsmen were brought in to carve elaborate stonework and create vaulted ceilings in the Great Hall. The island itself presented enormous challenges. The seven acres of rocky terrain offered little soil, so Bourne had his team bring over two thousand loads of topsoil from Canada, ferrying it across the water to create gardens. The construction cost just under five hundred thousand dollars, approximately thirteen to fifteen million in today’s currency.

The castle rose five stories high, crowned by a clock tower that stood even taller. Four enormous clock faces, each six feet in diameter, looked out over the river in all directions. Inside, the castle contained twenty-eight rooms, ten fireplaces, eight bathrooms, and a labyrinth of secret passageways. When visitors arrived by boat at one of the island’s three boathouses, the northern boathouse could accommodate Bourne’s hundred-foot steam yacht.

They climbed flagstone steps to a massive wooden door and entered the Great Hall, measuring thirty-nine by thirty-three feet with ceilings soaring overhead. Vaulted ceilings were elaborately carved by Italian masons. Sturdy stone pillars and archways lined the room. A large marble fireplace dominated one wall, and standing guard, exactly as described in Scott’s Woodstock, were suits of armor, Norman foot soldiers holding great swords and maces, forever vigilant.

Flagg had pulled a passage directly from the novel to inspire the room: war were buff jackets or shirts of mail, round bucklers with spikes in the center, holding great swords or maces like military guards on duty. But the real marvel wasn’t what you could see. The library, accessed through an archway off the great hall, was paneled entirely in walnut. Next to the marble fireplace there was a panel concealing the entrance to a network of hidden corridors.

At one time, pulling a specific book from a nearby shelf would trigger a mechanism, causing the panel to swing open and reveal the beginning of a labyrinth that ran throughout the entire castle. These corridors wound through the walls, connecting rooms, allowing movement from floor to floor without being seen. They weren’t built for drama. They served a practical purpose: they allowed servants to move through the house without disturbing the Bourne family and their guests.

Staff could slip through the walls, emerge quietly into rooms, check whether drinks needed refilling or the next course should be served, and then vanish back into the passages like ghosts. In the drawing room, a portrait of King Charles II of England hung over the marble fireplace. The portrait could be tilted back from behind, allowing someone hidden in the walls to peer into the room and spy on the guests. Viewing grates were built into walls throughout the castle for the same purpose.

The breakfast room, added later, featured large Gothic windows on three sides framing the river’s beauty. Ships in the International Shipping Channel passed remarkably close to the south side of Dark Island, only about a hundred feet away. The kitchen sat in a service wing with views of the Canadian shoreline, connected to the formal dining room above via a dumbwaiter and spiral staircase. A tunnel also linked the two spaces, allowing staff to deliver food without being seen.

For Frederick, his wife Emma, and their children, Dark Island was paradise. The family had lost three children to illness and accidents: Frederick Jr. , Louisa, Kenneth, and Helen all died young. But nine survived: Arthur, May, Marian, Alfred, Florence, George, Marjorie, and Howard.

The Bournes were obsessed with boats and yachting. Frederick served as Commodore of the New York Yacht Club from 1903 to 1905, sponsoring an entrant in the America’s Cup race. He owned numerous steam vessels, some of which can still be seen at the Antique Boat Museum in Clayton, New York. At Dark Island, the family kept five motorboats, three rowing skiffs, and two canoes at any given time.

They owned two-thirds of nearby Ice Island, using it for hunting duck and pheasant. Private trains brought hunting parties of up to fifteen guests from New York City for weekends at the castle. Fishing was a constant pastime, the waters around Dark Island perfect for sport fishing, with depths varying dramatically, largemouth bass and northern pike abundant. The castle hosted elaborate parties.

Frederick’s neighbor on Inglenook Island was the famous painter and sculptor Frederic Remington, who reportedly sent flowers to welcome the new neighbors upon completion of the castle. Cornelius Vanderbilt and Vincent Astor were among those who visited. J. P.

Morgan himself was a friend and correspondent. The elite of the Gilded Age sailed up to Dark Island’s boathouses, climbed the stone steps, and entered a world of luxury, secrecy, and architectural wonder. But even in paradise, shadows were gathering. Emma Sparks Keeler Bourne, Frederick’s beloved wife, was the granddaughter of Commodore Davidson, one of the founders of the New York Yacht Club.

She had married Frederick on February 9, 1875. In 1916, her health began to fail, and she died. The official cause was listed as natural causes, but her death devastated Frederick. After forty-one years of marriage, he was alone.

In 1918, just two years later, tragedy struck again. Howard Davidson Bourne, one of Frederick’s surviving sons, died at the age of twenty-five. He had never married. The cause of death was listed as illness.

By early 1919, Frederick was sixty-seven years old. He had retired from the presidency of Singer fourteen years earlier, though he remained on the board of directors. He had more money than he could ever spend, estates, yachts, automobiles, including a 1906 Mercedes-Benz. He loved to drive at dangerous speeds and was once arrested for going twenty-five miles per hour in New York City, a scandalous velocity at the time.

But he had lost his wife and his son, and the world that had made him wealthy was changing rapidly. World War I had just ended. The Roaring Twenties were about to begin. Frederick fell ill in the late winter of 1919.

For several months his health deteriorated. He was cared for at Indian Neck Hall, his massive Long Island estate, where Emma had also died. On March 8, 1919, the day before his death, Frederick added a codicil to his will. He left one hundred thousand dollars to the Cathedral of St.

John the Divine in New York City and made thirteen other substantial bequests. On March 9, 1919, Frederick Gilbert Bourne died. The official cause was listed as exhaustion and uremic poisoning, kidney failure. He was buried four days later, on March 13, with a funeral attended by the most powerful men in America, including William Avery Rockefeller Jr.

, Cornelius Neely Vanderbilt III, and J. P. Morgan Jr. His estate was valued at between forty-two and forty-three million dollars.

And this is where the story takes its darkest turn. Frederick left his vast fortune to be divided equally among his seven surviving children. On paper, this seemed fair and straightforward. In reality, it ignited a legal war that would last for years.

The children could not agree on how to distribute the estate. Arthur, the eldest surviving son and a director and treasurer of Singer Manufacturing Company, had his own ideas. The daughters had their own claims. George, who would eventually become president of Singer himself, sided with various factions at different times.

Alfred maintained a quieter role but was no less invested. A newspaper at the time quipped that the Bourne children seemed happier to share their inheritance with their lawyers than with each other. Dark Island itself became a particular point of contention. In the summer of 1919, just months after Frederick’s death, two of his daughters, Marjorie Bourne and May Strassburger, bought out their siblings for $389,000, becoming the new owners of the castle and island.

This was far less than the property was worth. In November 1921, Marjorie filed a lawsuit against her brother Arthur in New York Supreme Court, accusing him of fraud related to the sale of Dark Island. The case made headlines. Eventually the cases were settled, though exactly how remains murky.

Marjorie retained title to Dark Island, and in 1921 her sister May and May’s husband Ralph Beaver Strassburger gave Marjorie lifetime use of the island. In December 1926, Marjorie Bourne married Alexander Dallas Thayer, known to friends as Alec. He was forty; she was thirty-six. Alec was a noted tennis player who had competed in several matches at the U.

S. Open during the 1920s. Marjorie was a society woman with a taste for luxury and a sharp mind for business. Together they transformed Dark Island from a hunting lodge into a true summer home.

They made additions to the castle, building a third-story apartment over the piazza and converting the original wooden piazza to stone to support the new wing’s weight. They constructed a tennis court on the edge of the island, surrounded by water on three sides. For Alec’s birthday in 1928, Marjorie commissioned a squash court on the north side, complete with a sports therapy room. And then there were the rumors.

The 1920s in America were defined by Prohibition, the nationwide ban on the manufacture, sale, and transportation of alcoholic beverages. Rum running, the smuggling of liquor from Canada and the Caribbean into the United States, became a multi-million-dollar industry. Dark Island sat only a few yards south of the Canada–United States border, which ran right through the St. Lawrence River.

On the Canadian side, liquor was legal. On the American side, it was forbidden. Local legends persist to this day that Marjorie and Alec Thayer allowed Dark Island to be used for rum running. The hidden corridors, the boathouses, the dungeon all would have made ideal storage for contraband.

There is no definitive proof. The Thayers were never arrested, never charged, never publicly accused. But the whispers persisted. Whether or not the rumors were true, the Thayers lived well.

They entertained lavishly. They maintained not just Dark Island but also three yachts elsewhere, plus the five motorboats, three rowing skiffs, and two canoes kept at the island’s boathouse. They spent thirty-six summers at Dark Island, their lives a seemingly endless summer of tennis, boating, fishing, and parties. But even this chapter would come to an end.

On December 27, 1961, Marjorie, now seventy-one years old and with no children, sold Dark Island to La Salle Military Academy for less than one hundred thousand dollars. It was a gift really, a final act of generosity. After Frederick’s death, his estate at Indian Neck Hall had been sold in 1926 to the Brothers of the Christian Schools, a Catholic order, and converted into La Salle Military Academy. Now Marjorie was giving them Dark Island as well.

In 1962, at age seventy-two, Marjorie died. Alec outlived her by six years but never returned to Dark Island. He died in 1968, and with his death the last direct connection between the Bourne–Thayer family and Dark Island was severed. The Brothers of the Christian Schools had no idea what to do with a medieval castle on a remote island in the middle of a river.

The logistics of maintaining a property accessible only by boat, with no running water from municipal sources, relying on generators for electricity, freezing solid in winter, were insurmountable for a school with limited resources. For three years, from 1962 to 1965, Dark Island sat largely abandoned. Pipes froze and burst. Wallpaper peeled.

Dampness crept into the rooms. Some furnishings were removed, some stolen, some rotted where they sat. In April 1965, the Christian Brothers sold Dark Island for thirty-five thousand dollars to the Harold Martin Evangelistic Association, a religious charity established by Dr. Harold George Martin, a former chaplain to the Royal Canadian Air Force.

Dr. Martin was born in Quebec but had Norwegian ancestry; his grandfather’s original family name was Martin Yorstrud. When Dr. Martin and his wife Eloise took possession, they renamed it Yorstrud Castle.

They planned to use it as a private retreat for ministers and missionaries. They converted the breakfast room into a chapel and held religious services there every Sunday morning during the summer, opening them to the public. The arrangement was idyllic at first, but complications soon arose. Dark Island had been designated tax-exempt when owned by the Christian Brothers because it was owned by a religious institution.

When the Martin association took over, they assumed the status would continue. Neighbors challenged it, contending the Martins were using the property not for religious purposes but as their own private summer residence. The dispute went to court. Dr.

Martin defended himself, arguing that because he and Eloise offered religious services every Sunday morning open to all, the property qualified for tax-exempt status. The court agreed, and the Martins won. But the victory came at a cost. The legal battle put Yorstrud Castle in the public eye, and rumors began to circulate.

The castle’s name change confused visitors and locals alike. By 1985, health issues meant the Martins could no longer visit regularly. They put the castle on the market for five million dollars. During the late 1980s and early 1990s, advertisements appeared in high-end real estate magazines suggesting the castle could be used as a private residence, corporate retreat, or hunting lodge.

Interest came from as far away as Japan. Michael Jackson himself, at the height of his fame, made an offer to buy the castle. The Martins turned him down. For decades the castle remained unsold, and the decline accelerated.

Theft became a problem. Original fixtures, furnishings, and artifacts disappeared. Maintenance was expensive and ongoing. The generators needed constant repair.

The heating systems failed. The secret passageways became outright dangerous. Stories spread about people getting lost in the maze, unable to find their way out. The dungeon took on an even darker reputation.

Finally, in 2001, the castle found new owners. Dark Island Tours, Inc. , a venture led by German businessman Farhad Vladi and two European business partners, purchased the property. Vladi operated Vladi Private Islands GmbH, a Hamburg-based real estate company specializing in selling islands around the world.

The new owners undertook an extensive restoration, stabilizing the structure, repairing critical damage, and adapting the castle for tourism. In 2003, tours began. Unlike Boldt Castle, which had become a tourist attraction decades earlier, Dark Island had always remained a private residence until this moment. Much of the original character remained.

Many of the Bourne–Thayer furnishings stayed in place. The library still held books from the family’s personal collection. The castle’s name was changed back to Singer Castle, honoring Frederick Bourne’s connection to the Singer Manufacturing Company. In 2006, Dark Island was listed for sale through Sotheby’s International Realty for twenty-two million dollars.

Later listings raised the price to $24. 5 million. The castle remained on the market even as tours continued. Today, Singer Castle attracts approximately thirty-five thousand visitors per season.

Guided tours lead guests through the great hall, library, drawing room, clock tower, and portions of the hidden corridor network. The royal suite, occupying one wing of the castle, is available for overnight stays. The castle has also become a popular wedding venue. To stand in Singer Castle today is to stand at the intersection of American ambition and American tragedy.

The stones were quarried by immigrant laborers working for wages Frederick Bourne could have paid with pocket change. The hidden corridors were built so that working-class servants could remain invisible, moving through the house like ghosts while the wealthy pretended they didn’t exist. Frederick Bourne was a self-made man who rose from poverty through intelligence and hard work. He was charitable to his community, giving money to build fire stations and improve railroad infrastructure.

He believed in making sewing machines affordable for ordinary families. But he also accumulated wealth on a scale difficult to comprehend, entertaining in rooms that cost more to furnish than most families would earn in a lifetime. And when he died, his children fought over his fortune with a greed that shocked even the jaded newspapers of the 1920s. Indian Neck Hall still stands, but not as a family home.

It became La Salle Military Academy and is now owned by St. John’s University. In 2016, it was sold again to the AMD Education Group for $22. 5 million.

The Bourne family hasn’t owned it for over a century. William Kissam Vanderbilt’s Idle Hour was also converted to educational use and is now part of Dowling College. The grand ballrooms where Bourne and Vanderbilt entertained are now classrooms. And yet there is something fitting about Singer Castle’s survival.

Unlike Indian Neck Hall, Dark Island remained in the Bourne–Thayer family for forty-three years after Frederick’s death. Marjorie and Alec Thayer loved the castle and lived there every summer for nearly four decades. When they could no longer maintain it, they gave it to an institution they trusted. Today’s incarnation as a tourist attraction ensures the castle will survive, turning an exclusive monument to wealth into something approaching a public resource.

The Westminster chimes still ring out across the water. The waves crash against the rocky shore. Tourists take photographs and leave. The castle remains beautiful and hollow, a shell inhabited only by echoes of laughter from a century ago, whispers of servants long dead, and the sound of footsteps that could be visitors or could be ghosts.

Impossible to tell which, and ultimately impossible to care. The castle endures, but what it preserves is not Frederick Bourne’s dream of permanence. It preserves instead the lesson he learned too late: that stone outlasts ambition, that buildings outlast builders, and that the only thing more tragic than being forgotten is being remembered for what you built rather than who you were.