Philips ConnorThere is something unsettling about places where people once lived but no longer do. Ruins pull at our curiosity, whispering stories of lives that came before. Islands, though, take this fascination and twist it into something darker.
Cut off by water, they become pressure cookers of danger—whether from toxins we left behind, structures we abandoned, or nature reasserting itself in brutal ways.
Some of these islands will kill you within minutes. Others work slowly, contaminating your cells over years. What they share is a warning: humanity’s fingerprints do not fade easily, and nature does not forgive our mistakes.
This is not a travel bucket list. Most governments have sealed these places off for good reason. What follows is a look at ten islands where the wrong step, the wrong breath, or simply being there at all could end badly.
Quick Reference Guide
| Rank | Island Name | Location | What Makes It Deadly |
|---|---|---|---|
| 1 | Ilha da Queimada Grande | Brazil | Venomous pit vipers (critical density) |
| 2 | Bikini Atoll | Marshall Islands | Radiation in soil and food chain |
| 3 | Gruinard Island | Scotland | Weaponized anthrax (historical testing) |
| 4 | Poveglia Island | Italy | Plague mass graves throughout soil |
| 5 | Hashima Island | Japan | Structural collapse and airborne asbestos |
| 6 | Vozrozhdeniya Island | Central Asia | Soviet bioweapons residue |
| 7 | North Brother Island | USA | Collapsing quarantine hospital ruins |
| 8 | Fort Alexander | Russia | Former plague lab with structural decay |
| 9 | Whakaari | New Zealand | Active volcano, unpredictable eruptions |
| 10 | Bouvet Island | South Atlantic | Extreme isolation and hypothermia risk |
10. Bouvet Island
Norway claims this chunk of ice in the South Atlantic, but claiming and controlling are different things. Bouvet sits more than 1,000 miles from anything else, locked under glaciers that cover nearly the entire surface. The weather is Antarctic—wind, cold, and more cold. Landing here means fighting cliffs, pack ice, and seas that treat small boats like toys.
The real danger is not what is on the island. It is what happens when something goes wrong and nobody can reach you. A twisted ankle becomes life-threatening. Equipment failure turns fatal. In 1964, a British team found an abandoned lifeboat sitting on one of the few ice-free spots. For years, people spun theories—lost whalers, mysterious disappearances. Turns out, Soviet scientists had ditched it in 1958 when they barely escaped by helicopter as the weather turned. Even prepared expeditions with resources struggle here.
Bouvet does not attack. It just waits for you to make a mistake, then makes sure that mistake is your last.
9. Whakaari (White Island)
Off New Zealand’s coast, Whakaari breaches the surface like a warning. This is not a dormant volcano. It has been New Zealand’s most active for forty years, venting toxic gases and occasionally exploding without much notice.
People tried mining sulfur here in the early 1900s. In 1914, a landslide swallowed ten miners. The operation shut down. But the volcano kept going. On December 9, 2019, tourists were walking the crater when superheated water beneath the surface flashed into steam and exploded outward. Twenty-two people died. Others suffered burns so severe they spent months in treatment.
Scientists monitor Whakaari constantly, measuring gas, watching for ground shifts. None of that mattered in 2019. The eruption happened too fast for warnings to save anyone. Fumaroles in the crater hit temperatures above 700 degrees Celsius. Sulfur dioxide pours out continuously. The island sits there, breathing heat and poison, daring anyone to think they can predict it.
8. Fort Alexander
This artificial island fort sits in the Gulf of Finland, looking like something from a gothic novel. Built in the mid-1800s as a naval installation, it was converted in 1897 into a research lab focused on epidemics. The nickname “Plague Fort” stuck for obvious reasons.
The Imperial Institute of Experimental Medicine worked on serums for tetanus and cholera, but their plague research killed people. Between 1904 and 1907, three staff members contracted the disease. Two died, including the director. Bodies were cremated in the fort’s own furnaces to prevent the infection from spreading. That detail—burning corpses on-site—tells you how desperate containment efforts became.
The fort closed in 1917. Now the masonry is crumbling, and heavy sections of ceiling and wall threaten to collapse. But the bigger question hangs in the stale air: what else is in there? Forgotten samples, residual contamination in the walls, equipment that nobody properly decontaminated before walking away? Probably nothing viable after a century. Probably.
7. North Brother Island
You can see Manhattan from North Brother Island. The skyline glitters across the East River while this forty-acre plot rots in silence. From 1881 to 1943, Riverside Hospital quarantined people with contagious diseases here. Mary Mallon—Typhoid Mary—lived and died on this island, a healthy carrier locked away for public safety.
After the hospital closed, the city tried using the buildings for veterans’ housing, then a rehab center. Nothing stuck. By 1964, everyone left for good.
Now twenty-five buildings are disintegrating. Floors sag and collapse without warning. Concrete facades peel away. Roofs have caved in. But what makes the island nearly impossible to navigate is the vegetation. Nature has gone wild here, creating a sanctuary for Black-Crowned Night Herons and other wading birds. The undergrowth hides unstable ground, sharp debris, open pits. Walk through that tangle and you might punch through a floor before realizing there was a floor.
The city keeps it closed to protect both people from injury and birds from disturbance. Sometimes abandonment creates something worth preserving, even if getting there could kill you.
6. Vozrozhdeniya Island
The Soviets picked an island in the middle of the Aral Sea for their biological weapons testing, figuring isolation would contain whatever horrors they unleashed. From the 1930s through 1992, they tested weaponized anthrax, plague, smallpox, and tularemia. Some strains were genetically modified to resist antibiotics, turning treatable diseases into death sentences.
Then the Aral Sea started shrinking. Soviet irrigation projects drained the water faster than rain could replace it. By the early 2000s, Vozrozhdeniya was not an island anymore—it had become a peninsula. The natural containment barrier disappeared.
Contaminated dust from anthrax burial pits could now blow into populated areas. In 2001, the United States funded a decontamination effort that cost millions and focused on destroying anthrax spores still viable in the soil. That intervention happened because the danger was real and immediate, not theoretical.
When your bioweapons dump connects to the mainland and the wind starts kicking up spores, isolation stops being a defense. It becomes a timer.
5. Hashima Island (Gunkanjima)
Hashima looks like a battleship from a distance, hence the nickname Gunkanjima. Up close, it is a monument to how fast industrial civilization can collapse. Mitsubishi ran an undersea coal mine here, packing over 5,000 people onto a tiny island by 1959. When Japan switched to petroleum, the mine closed in 1974. Within three months, the island was empty.
The concrete high-rises were built to withstand typhoons and salty sea air. They are failing anyway. Walls buckle, floors drop away, and entering any building means gambling that it will not come down on you.
But the structural danger is just what you can see. The invisible threat is asbestos, which was used throughout the construction. As buildings decay, they release fibers into the air. Breathe that in and you are looking at cancer risk that does not show up for decades. Air samples near collapsed sections confirmed asbestos presence.
Hashima also carries moral weight. During World War II, forced laborers from Korea and China worked the mines under brutal conditions. Many died. The island is a grave as much as a ruin.
4. Poveglia Island
Poveglia sits in the Venetian Lagoon, small and cursed by its own history. During Black Death outbreaks, Venice used it as a dumping ground for plague victims. Bodies were transported, burned, or buried in mass graves. Estimates suggest 160,000 people ended up here over the centuries.
The folklore that half the soil is human ash is not entirely folklore. Archaeological evidence backs it up. The ground is unstable because it is layered with remains. Disturbing it means encountering bones, ash, and potentially residual biohazards from hastily constructed plague pits.
In 1922, the island was repurposed as a mental asylum. Legends claim a doctor performed crude lobotomies and other experiments before throwing himself from the bell tower. The asylum closed in 1968, and the buildings have been rotting since.
Poveglia combines infrastructure collapse, contaminated soil, and a history dark enough to make trespassing feel wrong on multiple levels. The island does not need ghosts to be haunted. The ground itself is enough.
3. Gruinard Island
During World War II, Britain needed to test whether anthrax could be weaponized effectively. Gruinard Island, off the Scottish coast, became the testing ground. They used the Vollum 14578 strain of Bacillus anthracis, detonating bombs above sheep to measure lethality and dispersal. The tests proved that anthrax could render an area uninhabitable for decades.
The island was quarantined for nearly fifty years. Anthrax spores are extraordinarily resilient, surviving in soil through weather, seasons, and time. Decontamination finally began in 1986, requiring 280 tonnes of formaldehyde solution sprayed across every surface. After placing healthy sheep on the island and monitoring them, officials declared it safe in 1990.
Then in March 2022, a wildfire tore across Gruinard, burning from end to end. Officials downplayed it, but fire introduces uncertainty. If heat or soil disturbance degraded the formaldehyde layer, spores buried deep might re-aerosolize. Nobody knows for certain. The wildfire did not prove the island is contaminated again, but it raised enough doubt to keep Gruinard in the conversation about dangerous places.
Anthrax does not care about declarations of safety. It waits.
2. Bikini Atoll
Between 1946 and 1958, the United States detonated twenty-three nuclear devices at Bikini Atoll in the Marshall Islands. The indigenous Iroij people were removed. The 1954 Castle Bravo test—a hydrogen bomb 1,000 times more powerful than Hiroshima—spread radiation across the region.
The air and water are clean now. The problem is the soil. Cesium-137, with a half-life of about thirty years, has woven itself into the ecosystem. Plants absorb it from the ground. People eat the plants. Studies show that internal radiation exposure from food contributes 85 to 90 percent of total radiation risk for anyone living on the northern atolls.
Tests on coconuts and pandanus fruits—staples in Marshallese diet—found contamination levels exceeding European Union and Japanese safety standards. On Bikini Island specifically, only three out of forty-seven coconut samples tested below Japan’s acceptable limit. Thirteen pandanus fruits exceeded the EU threshold of 600 becquerels per kilogram.
Cesium-137 in Bikini Atoll Foods
| Food Item | Island | Safety Finding |
|---|---|---|
| Mixed Fruits | Bikini Island | Above Japanese and EU standards |
| Pandanus Fruits | Bikini Island | 13 samples exceeded 600 Bq/kg EU limit |
| Coconuts | Bikini Island | Only 3 of 47 samples met Japan’s standard |
The contamination is not going anywhere soon. Remediation efforts like applying potassium fertilizer can help, but resettlement remains impossible without sustained intervention. The land looks fine. It will just kill you slowly if you try to live off it.
1. Ilha da Queimada Grande
Snake Island sits thirty miles off São Paulo, Brazil. It is home to the Golden Lancehead pit viper—Bothrops insularis—and nothing else of consequence. When sea levels rose after the last Ice Age, the snakes were cut off from the mainland. They adapted by hunting migratory birds in trees instead of ground prey. This evolutionary pressure produced a venom three to five times more toxic than mainland relatives. A bird struck by this venom dies before it can fly away.
The island is 106 acres. Estimates put the snake density at roughly one per square meter in forested areas. You cannot walk here without encountering multiple vipers. Each bite delivers fast-acting venom that causes rapid tissue destruction. There is no antivenom readily available because the species is isolated to this one location.
The Brazilian Navy has banned all public access. The prohibition protects people from agonizing death and protects the critically endangered vipers from poachers. Some dangers are biological experiments you can study from a distance. Ilha da Queimada Grande is a death trap you simply avoid.
Conclusion
These islands tell different versions of the same story: isolation amplifies danger. Some threats come from geology—volcanoes that erupt without warning, climates that freeze you solid. But the worst dangers are the ones we made ourselves. Weaponized anthrax that survives in soil for fifty years. Radiation that contaminates the food chain across generations. Industrial toxins released as buildings crumble.
The restrictions keeping people away from these places are not bureaucratic overreach. They are acknowledgments of failure—our failure to contain what we created, and nature’s refusal to clean up after us. These islands are museums of consequence, teaching lessons that would be better learned without anyone setting foot on their shores. If you want to explore them, documentaries and research papers offer a safer route than boats and trespassing charges.