Debauchery in Brentford and man-eating crocs – the world's most fascinating river islands

From the biggest to the most crowded - via one straight from the pages of Gabriel Garcia Marquez - we go on the trail of 11 fascinating islands on rivers.

Marajó, Brazil

The world’s largest river island? It may well be Marajó, in the mouth of the Amazon. This wedge of rainforest covers an area of 15,500 square miles, making it the 35th biggest island on the planet. That’s about the same size as Switzerland. To demonstrate, below is an image of the European country transposed on top of Marajó (thanks to the fantastic website thetruesize.com).

The giant island was home to a pre-Columbian society, the Marajoara, that flourished between 800AD and 1400AD. Sophisticated pottery, including elaborately painted urns, vases and bowls showing plants and animals, has been found by archaeologists, and as many as 100,000 people lived here before the arrival of European colonisers. It is home to around 400,000 today, with around a quarter of those found in Breves, the largest settlement. Many villages are built on stilts as much of the flat island floods during the rainy season.

Tourists can reach Marajó easily enough from the city of Belém and can enjoy spotting scarlet ibis, cranes and herds of water buffalo. It is also a good place to surf the longest wave in the world: Pororoca, a tidal bore that travels up to 500 miles down the Amazon and into the Atlantic Ocean. It isn’t for the faint-hearted – you may have to dodge entire trees in the river, not to mention the piranhas.

Mompox Island, Colombia

Margarita Island, also known as Mompox Island, is the largest of many islands found in Colombia’s Magdalena River. The biggest lure for travellers in these parts is undoubtedly the sleepy town of Santa Cruz de Mompox, a World Heritage Site since 1995 thanks to its immaculately preserved colonial buildings.

The Spanish came here looking for gold in 1537, and wealthy merchant families from Cartagena arrived to trade at a safe distance from marauding pirates on the Caribbean coast. Spain’s grip on the region was ended by Simon Bolívar, who took Caracas in 1813 with an army recruited largely from Mompox. “If to Caracas I owe my life, then to Mompox I owe my glory," he later said.

Writing for Telegraph Travel earlier this year, Sarah Marshall said: “This riverside gem is reached only with patience and determination. Travelling by road and ferry (essentially a raft stacked with cattle lorries), it took me 11 hours [from Cartagena] but I was told the journey can be done in seven if the current of the River Magdalena isn’t too strong.

Fans of the Colombian author Gabriel García Márquez will love Mompox, she added – it bears an uncanny resemblance to Macondo, the fictional setting for One Hundred Years of Solitude.

“Myth and superstition twist through the streets and stifling heat shrouds everything with a dreamy haze," she said. "Standing below the wooden balcony of Santa Barbara church, where old women gather to pray during lightning storms, I fantasised about the ice brought to Macondo by Melquiades and his gang of gipsies. Iguanas scuttled into the shade of trees bowing into the river (a tributary of the Magdalena), where statues of Cristo Negro are presented to quell floods after heavy rains.”

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Boven-Digoel, Indonesia

From the sublime to the sombre. Boven-Digoel - a chunk of New Guinea in the midst of the Digul river - was used as a Dutch penal colony in the first half of the 20th century. Thousands of Indonesian nationalists and communists were sent here, with the impenetrable jungle and hostile neighbouring tribes making escape all but impossible.

Rudolf Mrazek, in his 1996 book Making Indonesia, writes: “Beyond [the camp] was a jungle as far as one could imagine. Nameless flowers and nameless trees. Savages reputed for cutting off heads and relishing human flesh. And Digoel crocodiles: darker coloured inmated consoled themselves that the beast ‘reportedly’ showed a preference for swimmers and sinkers of lighter complexion. Omnipresent and all-penetrating jungle. Before rain came, falling water was heard from afar, and then, often, the paths as well as exiles’ houses were knee-deep in water. Flying ants attacked the camp at regular intervals, storming the Petromax lamps, inmates, walls and ceilings, blackening everything. Cicadas started their deafening concerts exactly at five.

“Twenty attempts at escape were recorded at Boven-Digoel between 1927 and 1935. A third of these courageous (or foolish?) men, some of them guided by the pocket Kleine Bos School Atlas, got as far as the Australian part of the island, and one or two even to the Thursday Archipelago. But that was the farthest they got. All ended up either eaten by jungle beasts or returned to the camp by friendly authorities of the British Commonwealth.”

New Guinea, now split between Indonesia and Papua New Guinea, is still associated with jungle tribes and uncharted wilderness. The chief attraction in the Indonesian half is the archipelago of Raja Ampat, part of the “Coral Triangle” and one of the world’s most coveted dive sites.

Islands have long been used as prisons, of course. Among the most famous are Alcatraz, Robben Island and Devil’s Island, a French penal colony off French Guiana (all are now tourist attractions).

Brentford Ait, UK

You don’t have to travel far to find a fascinating river island. The Thames is filled with them.

Now uninhabited, with no buildings, Brentford Ait was once home to the notorious Three Swans pub. Fred S. Thacker’s “The Thames Highway – Locks and Weirs”, published in 1920, explains: “In March 1811 one Robert Hunter of Kew Green described the island to the city as ‘a great Nuisance to this parish and the Neighbourhood on both sides of the River.’ It contained a ‘House of Entertainment, which has long been a Harbour for Men and women of the worst description, where riotous and indecent Scenes were often exhibited during the Summer Months on Sundays’.” It is now covered with willows, planted to obscure the Brentford gasworks from the view of Kew Gardens.

Then there’s the Isle of Sheppey, an estuary island whose name means “Isle of Sheep" in ancient Saxon. It has the distinction of being one of the few parts of Britain to have been occupied by an overseas power since the Norman invasion. A Dutch fleet captured it in 1667, before clearing off after a few days with supplies, ammunition and guns. It played an important role in the early history of British aviation, being home to Lord Brabazon's Royal Aero Club and the Shellbeach Aerodrome, and possesses Britain's only established scorpion population, brought to the island on board a ship in the 19th century.

And what about Fry’s Island? Accessible only by boat, it is best known as the location of a duel in 1163 between Robert de Montfort and Henry of Essex, the standard bearer to Henry II. According to W.M. Childs's The Story of the Town of Reading (1905), the quarrel arose when, during a battle with the Welsh, Henry of Essex allegedly dropped the standard and cried out falsely that the King has been slain – a coward’s act, declared de Montfort. Essex and de Montfort were ferried to the island, where Robert “thundered on him manfully with hard and frequent strokes”. Henry fell, was presumed dead, and taken away by the monks of Reading for burial. But the monks found he was still very much alive, and under their care he recovered from his wounds and became a monk himself.

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Majuli, India

The Guinness Book of Records doesn’t recognise Marajó’s claim to being the world’s biggest river island. We assume that’s because it lies in a river estuary and is washed by the waters of both the Amazon and the Atlantic. Majuli, on the other hand, is lapped by nothing but river - the Brahmaputra, to be precise - and gets the nod from Guinness. It is found in the overlooked Indian state of Assam and measures 136 square miles (about the size of Malta, as shown below). But it was once far larger. Around a century ago, before erosion did its worst, it covered an area of 340 square miles.

“It is a sacred island, a gentle place of rice cultivation, pilgrimage, worship and monasteries,” wrote Trevor Fishlock for Telegraph Travel back in 2008. “According to the myth of the goddess Sati, who was cut into many pieces, this is where her left breast fell to earth, giving life to the island. The monasteries date from the 16th century and there were once 65 of them.

“We lunched in a house that, like many in Majuli, was built on stilts to survive monsoon floods. And then it was time to get the ferry. Two sounds I carried with me from Majuli: the deafening clash of temple cymbals and the tinkle and trill of the monks’ mobile phones.”

?itny ostrov, Slovakia

Europe’s biggest river island lies between three rivers, the Danube, its Little Danube tributary, and the Váh, and covers 728 square miles. Confusingly, this makes it bigger than Majuli. Rather than worry too much about how Guinness works out its records, we’ll explain the island’s appeal, namely marsh fauna and flora. If species like the greater scaup, the velvet scoter, the great northern loon and the red-breasted merganser mean anything to you, start planning a trip. Slovakia’s capital, Bratislava, is the perfect base for exploring it. It’s an uncrowded alternative to Prague thanks to its grand civic architecture and hearty cuisine.

Manhattan, US

It’s not the biggest river island, but it is the most crowded. Manhattan’s 1.6m residents squeeze themselves into just 34 square miles, giving it a population density of around 47,000 per square mile. Only a handful of islands anywhere can trump it, with Colombia’s Santa Cruz del Isolte, a 0.1 square mile artificial island with a remarkable 1,200 citizens, topping the table.

Manhattan needs little introduction, being home to Wall Street, the headquarters of the United Nations, and four of the most visited attractions in the world: Times Square, Central Park, the Empire State Building and Grand Central Station.

Ever wondered what New York looked like before it was New York? The Big Apple actually began life as New Amsterdam, the capital of New Netherland, a Dutch colony conceived to exploit the North American fur trade. It is shown below in around 1650. The English captured it and renamed it New York in 1664. Native Americans, of course, occupied it long before that.

U Thant Island, US

One more from New York before we move on. This tiny artificial island is found in New York's East River, near the United Nations building. It was created in the early 20th century during the construction of a subway tunnel under the river: the rocks removed from underground were dumped here. In 1977, the island was leased from New York authorities by a group of UN employees and followers of the guru Sri Chinmoy, who served as a chaplain at the UN headquarters. They gave the island its current name (U Thant was UN secretary general from 1961-71) and planted vegetation on its surface. It is now a protected sanctuary for migrating birds.

Montreal Island, Canada

Few countries can boast more islands than Canada. The exact number is not known, but Georgian Bay contains the world’s largest freshwater archipelago, known as Thirty Thousand Islands, while the Saint Lawrence River, which forms part of the Canada-US border, contains thousands more. At the confluence of the Saint Lawrence and Ottawa rivers you’ll find the most frequently visited: the Island of Montreal, which forms a fair chunk of the city of the same name. Hannah Meltzer, writing for Telegraph Travel, proposed Montreal as a contender for the perfect city: a blend of Paris and Brooklyn where you can eat chips covered in gravy (poutine), spot street art and drink lashings of great coffee.  

So which country has more islands than Canada? Sweden. How many? 267,570, according to Statistics Sweden’s 2013 Islands in Sweden report. Just 984 are inhabited. The number, curiously, appears to be growing, its 2001 report listed 221,800. Either way, it makes Sweden the world's island capital.

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?le Saint-Louis, France

Just two natural islands interrupt the Seine as it flows through Paris. One is the ?le de la Cité, the city’s medieval heart and home to Notre Dame, Sainte-Chapelle, as well as a clutch of government institutions. The other is the ?le Saint-Louis?. Once upon a time Parisians stocked wood and grazed cattle there. It is now an elegant residential neighbourhood, with a spattering of hotels, restaurants and shops, as well as the impressive Eglise Saint-Louis-en-l'?le. An influx of foreign buyers has brought controversy in recent years, however, with a Qatari prince’s plans for one of the island’s grandest mansions, Hotel Lambert, the former home of Chopin and Voltaire, causing particular outrage.

Hajógyári Island, Hungary

This island in the Danube, to the north of Budapest, has a rich and varied history. It was occupied by the Romans, forming part of the ancient town of Aquincum, the capital of the province of Pannonia Inferior. Up to 40,000 people lived in Aquincum by the end of the 2nd century; they were entertained by two amphitheatres and public baths, while the rulers built fine palaces. The Romans abandoned in the fifth century, but many rediscovered remnants can still be seen just to the west of Hajógyári.

A millenia later, the island was used a hunting reserve by King Matthias Corvinus, who spent much of his reign waging war with neighbouring powers and subduing rebels, but is remembered fondly in Hungarian history books as Matthias the Just, a folk hero king who embraced the Italian Renaissance and liked to walk among his subjects in disguise.

Later Hajógyári became a centre for shipbuilding, earning it its current name (Hajógyári means “Shipyard”), as well as agriculture (carrot farming continued there until the 1960s).

Today it is a place of recreation and best known as the venue for the annual Sziget music festival. This year’s line-up (August 8-15) features Gordon Brown's favourite band: Arctic Monkeys, as well as Lana Del Rey, Gorillaz and The Kooks.