A 7,000-year deep freeze
The Hallstatt salt mines are the oldest in the world, with evidence of human activity stretching back 7,000 years. The constant low temperature of 8° Celsius and the high salt concentration create an environment devoid of microbial decay. This unique climate perfectly preserves organic materials that would otherwise disintegrate. For millennia, the mountain has been a time capsule, storing a direct record of prehistoric life.
Archaeological work has uncovered a collection of artifacts. In 1734, miners found the body of a prehistoric man, preserved by the salt since an ancient mining accident. Though he was reburied, records show his skin, hair, and clothing were intact. More recent finds include leather shoes, fur, ropes, and woolen textiles left by miners thousands of years ago. One of the most significant discoveries is a wooden staircase built around 1344 BCE. Dendrochronological analysis confirmed its age, making it the oldest known wooden staircase in Europe. It was returned to the mine after study, where the salt continues to preserve it. These objects show the details of the advanced and organized mining operations during the Bronze and Iron Ages. The period from 800 to 400 BCE is even named the "Hallstatt Age" because of the cultural evidence unearthed here.
Prehistoric gut check
The most detailed insights into the miners' lives come from their preserved feces. A 2021 study published in Current Biology analyzed the genomics and metabolomics of paleofecal samples from the mine. The salty and cool conditions preserved the ancient gut microbiomes with exceptional fidelity. Analysis of an Iron Age sample, approximately 2,700 years old, revealed a diet rich in whole-grain cereals like barley and spelt, supplemented with broad beans, fruits, and nuts.
The sample also contained abundant DNA from two specific fungi: Penicillium roqueforti and Saccharomyces cerevisiae. These are the microbes responsible for the ripening of blue cheese and the fermentation of beer, respectively. The genetic makeup of the fungi indicates they were intentionally selected and used for food processing, not the result of accidental consumption. This finding is the earliest molecular evidence for the consumption of both blue cheese and beer in Europe. It demonstrates that Iron Age miners in Hallstatt possessed a sophisticated knowledge of fermentation. They were not consuming raw products but were creating complex, processed foods to achieve specific flavors and for preservation.