Cellars are critical to the story of Pilsner Urquell
The bottom-fermenting method used to brew and keep the world-famous golden beer relies on a constant cool temperature – 5 to 8 degrees Celsius – all year round, and before the days of refrigeration that meant the beer had to be brewed and stored underground.
The citizens of the Bohemian town of Plzeň, now part of the Czech Republic, have since the 13th century burrowed into the sandstone bedrock to create extra living and working space, and to provide storage for both food and beer.
When the burghers of Plzeň decided in 1839 to build their own town brewery, they also carved out a network of cellars underneath the brewery, and the first batch of Pilsner Urquell in 1842 was fermented and stored in the cellars using large wooden barrels.
At that time, the capacity of the cellars was 7,000 hectolitres; but the tunnelling continued well into the 20th century, and the final network now measures more than nine kilometres, with some areas as deep as 22 metres below ground level. As they carved out new tunnels, some of the workers added their own signatures and artistic decorations that can still be seen today.
To keep the original cellars at the required low temperature, a huge cooling hall was built. Stocked with ice blocks, the hall chilled the incoming flow of air to the cellars, and the melting ice created streams of cold water that flowed along gutters carved into the cellar floors.
In time, improved technology led to both artificial refrigeration and the steel beer vessel, the combination of which meant keeping wooden lagering barrels in underground cellars became redundant. This resulted in more and more Pilsner Urquell being produced in the brewery rather than in the cellars beneath it.
However, the Pilsner Urquell cellars have not fallen into disuse – far from it. Our brewmasters’ desire to keep their beer tasting as close to the original as possible led them to always brew some of their beer in the time-honoured way, down in the cellars and using the traditional huge wooden barrels. This parallel brewing allows a direct comparison between Pilsner Urquell brewed using modern and traditional methods. A panel of employees and former brewmasters conduct tastings of both products as each new batch is created.