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Cahills Crossing -

Cahills Crossing is located on the East Alligator River in Northern Territory, Australia. 

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Cahills Crossing -

People keep crossing it, despite the waters being infested with crocs. In fact, a 2016 survey found an average of 120 crocodiles in a 4-miles (6.4 km) stretch! 

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Congo River -

Formerly also known as the Zaire River, the Congo River is the second-longest river in Africa. The river is teeming with dangers along its 2,900 miles (4,700 km).

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Congo River -

Not only are there deadly animals such as crocodiles, hippos, and snakes, you also have to survive the rapids known as the Gates of Hell.

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Congo River -

And even if you manage to survive all of that, you'd still have to worry about cannibals from the Engombe tribe capturing you in a area known as "the abattoir."

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Rio Tinto -

This Spanish River is as close as it gets to being in Mars! Around 5,000 years of mining have contributed to its composition and dramatic color.

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Rio Tinto -

Rich in iron and heavy metals, Rio Tinto is extremely acidic. The water contains high amounts of iron and potassium sulfate compound, and methane.

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Rio Tinto -

But despite the extreme conditions, some microorganisms do live in the inhospitable river.

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San Juan River -

This Colombian river stretches for 236 miles (380 km). Its biggest danger is actually human, as the river is one of the country's major drug-trafficking routes.

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San Juan River -

Various armed groups patrol the area, including the National Liberation Army (ELN) guerrilla group. So, not the place for a relaxed boat trip!

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Citarum River -

The Citarum River in Indonesia is used by millions of people for irrigation, fishing, and as a source of drinking water.

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Citarum River -

But this is one of the most polluted rivers in the world, responsible for numerous diseases in the population, including cancer.

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Yellow River -

The first settlements around China's second-longest river date back to around 2100 BCE. But those looking to make the most of the fertile farmland on its margins had to battle the river's flood waters.

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Yellow River -

The Yellow River is indeed a wild beast. It has changed course 26 times and flooded over 1,500 times in the last 80-plus years. Millions of people have consequently died.

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Yellow River -

The Environment and Society Portal estimates that the Yellow River floods have killed more people than floods from the rest of the world's rivers combined!

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Niger River -

The Niger is the third-longest river in Africa, and indeed the main river of West Africa. It extends for about 2,597 miles (4,180 km).

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Niger River -

Flooding is the main danger of this river. Between 2012 and 2017 alone, it's estimated that around 2.5 million people had to leave their homes.

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Niger River -

In 2020, another 226,000 people had to relocate due to floods. Adding to the rising waters, there's also high levels of pollution and cholera outbreaks to worry about.

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Zambezi River -

This African river is home to around 90,000 hippos and 188,000 crocodiles, and other dangerous wildlife, such as river sharks.

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Zambezi River -

And if you happen to survive it all, you'd still have to worry about unexploded landmines and flooding. Yikes!

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The Ganges -

India's holy river is a pilgrimage site for hundreds of thousands of people every year. But there's more to the river than its spiritual importance.

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The Ganges -

The Ganges is also used for irrigation and to dump sewage. The result is extremely polluted water, teeming with deadly bacteria. Cholera outbreaks, for instance, still kill millions every year.

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Niagara River -

You're probably familiar with the Niagara Falls, itself quite dangerous. So much so that since 1850, some 5,000 people have been recovered from its base.

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Niagara River -

But the Niagara River has more dangers, including rapids and the 125-feet-deep (38 m) Niagara Whirlpool, which has claimed many lives over the years.

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The Bolton Strid (River Wharfe) -

This unassuming picturesque stretch of the River Wharfe in Yorkshire, England is a lot deadlier than it looks.

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The Bolton Strid (River Wharfe) -

In this section, the river goes from shallow to very deep, which means strong undercurrents, rocks, and underwater caves capable of trapping anyone who falls into it.

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Boiling River -

This tributary of the Amazon River can be found in Peru. Its temperature varies, but it frequently reaches up to 200°F (93°C).

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Boiling River -

That's hot enough to boil you! Local shamans believe the river is the home of the mythological serpent Yacumama.

Sources: (Grunge)

See also: The most jaw-dropping US caves you can actually explore

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