Costa Rica’s Cave of Death: no one returns alive!

3 min read

1 year ago Danilo

There is a statutory warning before you begin this journey into a cave in Costa Rica, and you may never return alive after entering it.
Yes, you read it right, as it kills anyone or anything that enters it.
The Recreo Verde tourist complex in Venecia de San Carlos is home to a tiny mountain cavern that has come to be known as la Cueva de la Muerte, or “The Cave of Death”, due to its peculiar ability to kill any creature that enters it.

Located on the edge of the Poas Volcano, it is only 2 meters deep and 3 long, which makes it a seemingly cozy refuge for insects, birds, and little creatures looking for a simply shelter.
However, appearances can be deceiving, as entering this tiny cavern results in an almost instant death.
Although the tiny cave looks harmless to the naked eye, it is filled with carbon dioxide, a colorless, odorless, tasteless gas but also extremely toxic and, to demonstrate just how lethal the Cave of Death actually is, local guides place a lit torch inside the cavern, that is extinguished instantly by the absence of oxygen and the high concentration of this toxic gas.

No one really knows exactly where the carbon dioxide in the cave comes from, but a number of researchers concluded that the organic nature of the gas is simply the result of mineral deposits subjected to high temperatures and pressures in the earth’s magma, where oxygen is absent.
Not by chance, the cave’s location is close to an active volcano may also have something to do with the gas, but one thing is for certain: scientists have found that The Cave of Death produces about 30kg of carbon dioxide every hour.
The lethal properties of this tiny cavern were discovered by accident during the building stages of the Recreo Verde complex, when one worker who got too close to the entrance started feeling sick, which led to a thorough investigation of the surroundings.
Either way, Its deadly reputation made the site one of the few commercial caves where visitors do not go inside.

The Cave of Death features several signs warning people not to enter it if they value their lives, but its small size and narrow entrance also make it very difficult to access by humans.
Moreover, the dense carbon dioxide (about 80 – 90 percent purity) usually stays on the bottom of the cave floor, making the place even more deadly to little animals, who begin to asphyxiate moments after entering the cave….