9 Crazy Lakes You Can’t Swim In

Written by Emmanuel Kingsley
Updated: June 24, 2023
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Key Points:
  • Lake Karachay, located in Russia, contains a dangerous level of radiation: about 600 roentgens. That’s dangerous enough to kill a human being standing by the shore for up to an hour.
  • Lake Victoria is known as the world’s most dangerous lake because of harsh storms and unpredictable weather conditions. 5,000 people a year lose their lives in this African lake.
  • Lake Vostok was hidden for about 14 million years under the glaciers of Antarctica until humans pierced the ice shield above the lake in 2012. Humans can’t swim in it due to its extremely cold temperature and high level of gas concentrates.

Nature is stunning and gorgeous. One of the most beautiful settings across the world is lakes. Tranquil and providing the opportunity for a dip in cooling waters, lakes provide both relaxation and the opportunity for some recreation via a good swim.

Yet, fair warning: not every lake is safe to get even close to! And it’s not just about the dangers of wild sea animals to worry about. If you’re interested in lake swimming, here are nine crazy lakes you can’t swim in.

Infographic of 9 Crazy Lakes You Can Not Swim In
Swimming in the waters of these lakes is dangerous and may lead to injury or death.

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1. Lake Karachay

Lake Karachay is highly polluted with harmful substances as a result of nuclear wastes that were emptied there.

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The crazy thing about Lake Karachay is not that it’s located in Russia, a current war zone in the world (honestly, that is the least reason not to go there for a quick dip). The crazy thing about the lake is it is highly polluted with harmful substances as a result of nuclear wastes that were emptied there. However, the Karachay Lake has not always been that way. Its pollution started in 1951 when a nuclear processing unit used the lake for waste dumping.

But that is not even the craziest fact about the lake. The lake is discovered to contain a dangerous level of radiation of about 600 roentgens that is dangerous enough to kill a human being standing by the shore for up to an hour. 

2. The Boiling Lake

Boiling Lake

The temperature of Boiling Lake is enough to cause a third-degree burn.


If you’re in Dominica, never go take a swim in the Boiling Lake. Why? From its name, you should be suspicious about your safety already. The lake is extremely hot and the temperature has been measured to be as high as 197 degrees Fahrenheit. That is hot enough to cause a third-degree burn if you stay in for as little as two seconds. But what is the mystery behind this boiling lake? Below the lake is hot magma completely submerged but actively heating the lake to a really high temperature.

3. Laguna Caliente  

Laguna Caliente

Laguna Caliente is surrounded by raging lava.


Have you ever heard of the Poas Volcano? That is exactly where the Laguna Caliente is. The name itself is Spanish meaning ‘Hot Lagoon’ when translated into English. From the name alone, you should already know by now why you can’t swim there; it’s hot and dangerous! But wait, there’s more.

Apart from being surrounded by raging lava, the lake itself is extremely acidic and it occasionally erupts. By the look of the lake, its ever-changing color is enough to discourage you from going in. If you are a visitor or a tourist in Costa Rica, swimming in the Laguna Caliente definitely isn’t something you should explore. 

4. Lake Victoria

According to reports, 5,000 people die on Lake Victoria annually.

©Stefan Haider/Shutterstock.com

Inhabitants of Tanzania, Uganda, and Kenya are familiar with the mystery behind Lake Victoria. But if you are not, you are about to find out more about it now. This lake, also known as Victoria Nyanza, experiences harsh storms and unpredictable weather conditions.

Unfortunately, this unusual weather has claimed the lives of some local fishermen whose boats capsized while fishing in the lake. Many say they can’t afford to invest in life jackets, or their boats are run-down. The fishermen may head out to fish in totally peaceful conditions, only to have a sudden storm hit when they are far from the shore. There’s also a lack of dependable weather services in the region to warn locals of impending danger. According to reports, 5,000 people die on the lake on an annual basis. This high death toll has led Lake Victoria to be called “the world’s most dangerous lake.”

5. Horseshoe Lake

Horseshoe Lake in California has killed people and, no doubt, animals when gas levels fluctuated.


If you ever have the opportunity to visit Horseshoe Lake in California, you will agree that it looks haunted. That’s because nearby are several dead trees covering a large expanse of land. But that’s not the crazy thing about the lake. The lake itself is dangerous because of the unpredictable fluctuation of the gas levels in the atmosphere. This fluctuation sometimes causes the carbon dioxide in the atmosphere to increase to a toxic level. Unfortunately, some lives were lost over the years due to this fluctuation.

6. Lake Vostok

Located on the iciest continent on the planet, Lake Vostok is difficult to spot from a plain surface

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Lake Vostok is not a usual lake to swim in. It’s a subglacial lake found in the remote continent of Antarctica. Until humans pierced the ice shield above the lake in 2012, Lake Vostok was hidden for about 14 million years under the glaciers of the cold continent. Humans cannot swim in it because of its extremely cold temperature and high level of gas concentrates (plus, it sits under 13,000 feet of ice!).

Scientists have compared the lake’s climate to that of the two moons; Europa and Enceladus. Interestingly, it is suggested that living organisms can hardly survive in it and only extremophile life can. That is to say, the lake could be a haven for ancient bacteria that’s long been cut off from the larger world.

7. Lake Kivu

Lake Kivu has the potential to “explode” and possibly kill millions of nearby residents.


Many tourists are moved by the pure beauty of lakes and their surroundings, and Lake Kivu is indeed a gorgeous sight. This lake in Rwanda is surrounded by a beautiful blooming green landscape. However, the lake itself is very dangerous. Lake Kivu holds incredible amounts of dissolved carbon dioxide and methane that has the potential to “explode” and kill millions of nearby residents. Lake Kivu isn’t the only lake on this list that has dangerous levels of gas underneath its waters. As you’ll see below, several lakes in Africa have had dangerous bursts of carbon dioxide that suffocated anyone nearby.

8. Lake Monoun

Lake Monoun is near a volcanic field and is unstable.

©Prosper Mekem / CC BY-SA 4.0, via Wikimedia Commons – License

If you are a first-time visitor, you may not suspect that there is any danger attached to Lake Monoun. While it looks like a harmless small lake, history tells a different story about it. Lake Monoun is near a volcanic zone and is quite unstable. It has once exploded before and the crazy thing is: the eruption was unpredictable. The 1987 explosion released a toxic level of carbon dioxide into the atmosphere, claiming the lives of  37 victims. So, if you are in Cameroon, Lake Monoun is not one of the places you should swim in.

9. Lake Nyos

Lake Nyos in Cameroon lies above magma which releases toxic levels of carbon dioxide.

©United States Geological Survey, Public domain, via Wikimedia Commons – License

Lake Nyos is another lake you shouldn’t swim in if you are in Cameroon. This body of water is above magma which releases toxic levels of carbon dioxide into the atmosphere. The toxic gas level is lethal to both humans and even animals. Besides, the lake has recorded an explosion that claimed the lives of 3,500 animals and nearly 2,000 people. So, it’s advisable for you to stay away from the lake if you are exploring nature in Cameroon. 

Summary of the 9 Crazy Lakes You Can’t Swim In

Here’s a review of some lakes with bizarre characteristics that make them bad choices for swimmers:

1Lake KarachayRussia
2The Boiling LakeDominica
3Laguna CalienteCosta Rica
4Lake VictoriaTanzania, Uganda, and Kenya
5Horseshoe LakeCalifornia
6Lake VostokAntarctica
7Lake KivuRwanda
8Lake MonounCameroon
9Lake NyosCameroon

In Contrast: Lake George Is the Cleanest in the United States

Lake George in the Adirondack Mountains is the cleanest lake in the United States and great for swimming!

©iStock.com/Amy Sparwasser

The photo featured at the top of this post is © Frostka/Shutterstock.com

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