Dunsthöhle Bad Pyrmont

The haze cave is located on the site of a former quarry in which Buntsandstein was broken. When the quarry workers came to a certain depth, they noticed a "haze" from which they fainted.

In the pit one found again and again dead birds and other animals. As the Pyrmont Fountain Doctor Johann Philipp Seip came to Pyrmont in 1712, he followed these apparitions. He came to the conclusion that it was sulfuric art, since carbon dioxide was not known at that time.

With the permission of Prince Friedrich Anton Ulrich to Waldeck and Pyrmont he had 1720 "build a stone vault over the steaming pit and build a small vaulted wall over there to set up a dry pool of sweat.

The strange behavior of the CO2 gas has impressed visitors since Seip until today.

It is one and a half times heavier than air, so it stays in the pit and responds mainly to air temperature and pressure. In the CO2 gas you get a feeling of warmth. At the same time, the temperature of the gas in the vapor chamber is considerably cooler in the summer at high air temperatures. In winter it is the other way around.

The explanation of this phenomenon is the circulation-promoting effect of the gas.

The building above the haze and the guardhouse were renovated in 2000 and the park was redesigned.
Source (regi-on.de/kultur-freizeit/freizeit-erholung/sehenswuerdigkeiten/62.htm)

The vapor cave should definitely be visited - the last natural spectacle of its kind in Europe.Only possible with a guided tour, the price is 1.50 euros for adults.Absolutely interesting, great tour with great explanations.
More is not revealed, so that the wow effect is greater!

The haze cave in Bad Pyrmont is a brick grotto from which carbon dioxide flows. After the Hundsgrotte near Naples was walled up after the Second World War, it is the only cave of this kind in Europe.
At the beginning of the 18th century, workers noticed that gas was escaping from the quarry rock. If they got near the gas leaks, they would faint after a while. When it rained heavily, the carbonic acid rose from the rainwater in the form of bubbles. Dead birds and other dead animals were often found near the gas wells. In 1712, the fountain doctor Johann Philipp Seip came to Pyrmont and got to the bottom of this natural phenomenon. Due to the suffocating properties of the gas, Seip initially assumed that the gas was sulfur gas.
Source: de.wikipedia.org/wiki/Dunsth%C3%B6hle