The community of Oberried is located in the Black Forest, in the middle of nowhere. But an ancient mining tunnel in the seemingly insignificant village is home to Germany's memory. Rock-hard granite makes up most of the Barbara mine rather than the hoped-for silver. Yet, it provides the best defense against earthquakes and nuclear disasters while also ensuring the ideal climate for preserving cultural artifacts. That's why important historical records from Germany, including the Cologne Cathedral's construction plans, have been kept here since 1975. To save space, the documents are not kept in their original form but on microfilm.

If properly stored, these microfilms will last for over 500 years and, best of all, can be deciphered at any time with a magnifying glass and a beam of light. Around 30,000 kilometers of film have already been stored in more than 1,400 canisters in the "hallowed halls." In a highly German manner, the containers are slightly modified steel beer barrels. In 2004, a bizarre art project was launched: 50 contemporary artists secretly filled containers with their work. If everything goes according to plan, the barrels will be opened by our descendants in the year 3504 – 1,500 years after the containers were sealed.