With about 71% of our planet’s surface covered in water and hundreds of thousands of islands dotting the oceans, it’s no surprise that many of these bits of land hold age-old secrets that continue to perplex historians and scientists. From the Frankenstein-like “Montauk Monster” of New York’s Plum Island to Easter Island’s curious moai statues towering in the middle of the Pacific, here are six of the world’s most fascinating islands and their mysterious stories.
Roanoke Island, North Carolina
Roanoke Island, located on the Outer Banks of North Carolina, is believed to have been inhabited by Native Americans for over 9,000 years. It wasn’t until 1584 that the first British settlers arrived on these tree-lined shores and established one of the earliest colonies in North America. However, the colony was short-lived, and the fate of these original British settlers remains unknown. Just two years after arriving, all 200 colonists vanished without a trace, leaving only a note — specifically, a word and half — as clues. Carved into two tree trunks near the colony were the cryptic letters “croatan” and “cro.” None of the settlers were seen or heard from again, and four centuries later, their disappearance and fate — and the meaning of their final words — is still one of history’s most puzzling mysteries.
Mont Saint Michel, France
The majestic Mont Saint Michel, dedicated to Saint Michael the Archangel, is one of France’s most beloved historic landmarks, drawing millions of visitors each year. The small tidal island off the coast of Normandy is dominated by a massive stone abbey built in the eighth century that became a powerful Benedictine monastery. But mystery persists about who exactly was responsible for this architectural wonder — and when it was actually built.
In recent decades, historians and archaeologists began digging a bit deeper to solve the puzzle. The eerily beautiful Underground Chapel of Our Lady, believed to be the oldest part of the monastery, is built of brick walls typical of buildings from the first millennium. However, scientists are still debating whether the Christian church first laid this foundation in the eighth century, or whether it was constructed hundreds of years later. More precise and sophisticated new technology has led researchers to believe that the latter is most likely true. But in 2016, a new team used a ground-penetrating radar (or georadar) to dig even deeper below the surface of this chapel and determined there had been no previous construction below. And so the location and fate of Mont Saint Michel’s original Christian church continues to intrigue.
Plum Island, New York
Located just over a mile off the coast of Long Island, Plum Island was made famous by New Yorker Nelson DeMille in his best-selling murder mystery novel Plum Island. In the decades since, rumors have swirled around the island’s government-owned and tightly-guarded laboratory. Was the lab responsible for birthing the Frankenstein-like “Montauk Monster,” whose carcass supposedly washed up on a nearby beach? And what about the ghost of poor Colonel Gardiner, the sole permanent resident of the island, buried here after dying of yellow fever in 1786 and now believed to haunt the lighthouse? Most pressingly, what exactly was the United States government doing here?
Officially, the U.S. Department of Agriculture ran the Plum Island Animal Disease Center (PIADC) to protect the country’s livestock population from infectious foreign diseases. It also once served as a bioweapons research facility. Whatever really happened here, the lab has shuttered and moved inland. Now, a strong local interest in protecting these shores has taken root, and the Preserve Plum Island Coalition is dedicated to creating and maintaining a wildlife sanctuary here instead — and to hopefully put a peaceful end to the island’s dark past.
Socotra, Yemen
Found 60 miles from the horn of Africa in the Gulf of Aden, the stunning island archipelago of Socotra is governed by Yemen. While some believe the land may have been part of the legendary missing continent of Atlantis, one thing is certain: Socotra today is a treasure-trove of natural wonders, where hundreds of endemic plant and animal species found nowhere else on Earth still thrive.
Most notable among these are the forests of hundreds of bizarre, umbrella-shaped dragon’s blood trees — some that are 1,000 years old — which get their name from their unique red sap. Myths of the trees’ origins are deeply rooted (pun intended) in this fertile soil; according to one local legend, the gnarled, thick trunks grew from the blood of a dragon injured in an elephant battle. While we may not know what explains their strange existence on this one island, the trees brought Socotra recognition as a UNESCO World Heritage Site, and their red sap is harvested by locals for its purported healing powers.
Malta
Among the many wonders you’ll find in the small but mighty Mediterranean archipelago of Malta are megalithic temples, ancient observatories (older than the pyramids of Egypt), and catacombs filled with curious elongated ancient skulls.
But one of Malta’s most enduring mysteries lies in the deep, deliberate parallel grooves in the earth. They criss-cross the islands in more than 150 locations, always running in pairs, and are believed to be older than any of the megalithic architecture. What were these tracks made by, what was their purpose, and where did they lead to? Some run right off the sides of cliffs, while others lead straight into the water. These tracks have even been found deep beneath the surface of the surrounding sea. Equally perplexing are Malta’s strange and unexplained steep stone steps carved into the cliff sides, including the stairs at Blata tal-Melh, and the stairs at Cirkewwa in Mellieha. Given how long they’ve been searching in vain for answers to Malta’s many mysteries, scientists many never quite know.
Easter Island, Chile
On Easter Island (Rapa Nui in the native language), there’s an unusual, permanent population of local celebrities: hundreds of intriguing, imposing stone monoliths called moai that dot this island 2,300 miles off the western coast of Chile. These towering hand-carved figures appear to have been standing watch, like stoic sentinels, over the barren island landscape for hundreds of years. But what is their purpose or meaning?
Historians aren’t sure exactly when and why the earliest Polynesian settlers paddled their long way to this remote island, how many years they lived here, and why their civilization collapsed. Based on the surrounding soil samples, a team of UCLA scientists hypothesized that the people who inhabited Rapa Nui may have hoped the statues could bring fertility to the soil, allowing critical food to grow. The island was believed to have lush vegetation and giant palm trees when settlers first arrived, but many trees were likely cut down for fire, construction, and to allow space for crops to grow. This led to an increasingly barren landscape and eroded the nutrient-rich soil, leaving the inhabitants hungry. By the time that the first Europeans arrived, on Easter Day in 1722, the land had little left to offer, and the civilization soon collapsed. However, some historians suspect humans could not solely be responsible for this level or speed of the civilization’s decline, so how exactly it disappeared remains a mystery.