Humanity's oldest alcoholic drink is being brewed underneath the Parisian streets, more specifically in the Paris Catacombs. Audric de Campeau has chosen the 2,000-year-old path consisting of caves, quarries, and tunnels stretching over 300km in Paris to brew mead, also known as honey wine.

De Campeau told BBC News that the catacombs served as the perfect spot for brewing the mead because the temperature is set at 14C, contains no vibrations or odors, and  humidity levels stay around 90 percent. To make mead, it must be fermented in a cool and peaceful location where the area is damp.

De Campeau visited the Catacombs when he was still an undergraduate at Sorbonne in Paris studying medieval philosophy. When he saw the Catacombs, he found that it was the perfect place to make his brew. He already started making wines at his parents' home in Champagne when he was 15 years old and would like to make mead as recognized like wines and champagnes in French menus.

As a beekeeper, he said, "My bees live 20m above Paris, while my mead lives 20m underneath." His beehives can be found up in the 18th-Century French Military Academy building where he stated his honey tasted like nothing else in the world.

The honey he collected from his city bees tasted of berries, lychees, blackcurrants, and citrus because of the diversity of Parisian trees. Furthermore, De Campeau said the honey is a lot less polluted than the countryside harvest because there aren't any pesticides. "The honey, and therefore the mead, is like a botanical taste of the city," he said.

De Campeau had his oak barrels built in Burgundy for the mead and tried fermenting it in sherry casks as well. The oak barrels permeated the drink with tannins and leather, and the sherry enhances the subtle cherries in the Parisian honey. He also worked with oenologists for the flavors of his drink.

Demand for his mead went through the roof as the hit TV series Game of Thrones made the drink famous. Meanwhile, De Campeau is not worried that mead will just become a fad drink because he considers the drink "timeless."