Located in the Northwest Region of Cameroon, Africa, Lake Nyos is one of the world’s deadliest bodies of water. Known locally as “the Bad Lake,” Lake Nyos was formed inside of a volcanic crater, meaning that high levels of CO2 are often released into the atmosphere over time.
However, this wasn’t the case for this particular lake. Instead of the gas gradually being released, the lake trapped the CO2 beneath the water. It was literally a ticking time bomb–just waiting to blow.
Then, on August 21, 1986, the most bizarre natural disaster in history occurred. It is known as a Limnic Eruption, which caused the lake to explode and trigger a small tsunami.
This wasn’t the worst of it. The explosion also sent a catastrophic wave of CO2 throughout the region, killing 1,746 people and more than 3,500 livestock animals in just minutes.
According to PBS:
The unfortunate villagers around Lake Nyos literally suffocated under the heavy poisonous cloud of gas.
After the catastrophe, the pristine lake turned a fiery red, a transformation that was caused by the iron at the bottom rising to the top.
The exact cause of the gas release at Lake Nyos is still a mystery.