Deadly snakes, spinning islands and swimming pigs: The 6 weirdest islands on the planet

The world is dotted with strange and captivating islands – some famous for their beauty, others for their bizarre or deadly secrets. From Brazil’s Snake Island, teeming with venomous snakes, to Scotland’s Gruinard, once a testing ground for biological warfare, these isolated places spark both curiosity and caution.

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Whether it’s the swimming pigs of the Bahamas, a mysteriously rotating island in Argentina, or the surreal biodiversity of Madagascar and Socotra, each has a story as unusual as the landscape itself. Here’s a look at some of the world’s most intriguing and unusual islands.

The world's weirdest islands

Snake Island

Snake Island is famous for its limbless reptiles. Ilha da Queimada Grande, to give it its Portuguese name, is a lump of rock sitting 33km off the Brazilian mainland. It has come to be known as Snake Island because of the thousands of venomous snakes that occupy its 43 hectares.

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Anthrax Island

Scottish Islands regularly feature in the world’s top holiday destinations. One, however, remains absent from all tourist itineraries: Gruinard.

This was once a haunt of fishermen and crofters. But by the mid-20th century visitors were prohibited and it became known as the island of death – due to what happened during WWII.

In 1942, with Nazi forces ascending, Prime Minister Churchill sought advanced tools of war to turn the tide. As part of the plan, the MoD came to Scotland to find land to test weaponry. The island was purchased, locals were banned and scientists from the MoD’s biological weapons facility at Porton Down arrived to carry out clandestine experiments. Their weapon of choice: anthrax, a deadly infectious bacteria produced from naturally occurring soil organisms.

Read the full story about Anthrax Island

Pig Island

Credit: Getty

An unusual welcome awaits visitors to Big Major Cay in the Bahamas. Moor your boat off the beach (which is the only way to reach this tiny, uninhabited island) and you are likely to be greeted by dozens of excited pigs bursting from the undergrowth and hurling themselves into the water before you can reach dry land.

These are not wild pigs but feral ones, and many a tale is told about how they got to Pig Island, as Big Major Cay has inevitably come to be known. One story goes that they are descended from animals stowed there by sailors of old, who never returned for them. Another is that they are the survivors of a shipwreck.

El Ojo

In the wetlands of the Paraná Delta, just north of Buenos Aires, there is a curious island known as El Ojo.

What's strange about it? To start with, it floats. It's also a near-perfect circle that sits inside a lake, which itself is circular. Stranger still, El Ojo appears to rotate and shift its position over time.

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From the air, this fusion of characteristics makes the island look like an eye – hence its name, El Ojo, which translates into English as 'The Eye'.

Madagascar

The island of Madagascar is a wildlife paradise filled with many beautiful species that can't be found anywhere else in the world. Plenty can be considered to be some of the weirdest living animals in the world, including the aye-aye, lemurs and the fossa.

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Madagascar is located roughly 400km off the eastern coast of Africa. The stretch of sea in between Madagascar and East Africa is called the Mozambique Channel.

Socotra Island

The desert island of Socotra lies off the coasts of Yemen and Ethiopia, and soils are thin and rain scarce. It's a hotbed of evolution with many weird-looking endemic species, from dragon’s blood trees (one of the weirdest trees in the world) to reptiles including the Chamaeleo monachus. Due to its exceptional biodiversity, Socotra was recognised as a UNESCO World Heritage Site in 2008.

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