In the mountain behind my home is a similar archive, the Barbarastollen. The documents stored there on microfilm in containers contain stuff like the original b

In the mountain behind my home is a similar archive, the Barbarastollen. The documents stored there on microfilm in containers contain stuff like the original building plans of the Cologne Cathedral, the Golden bull, the coronation certificate of Otto the Great, or Bach's handwritten manuscripts. https://en.wikipedia.org/wiki/Barbarastollen_underground_archive https://en.wikipedia.org/wiki/Barbarastollen_underground_arc... The German wikipedia page has some interesting photos: https://de.wikipedia.org/wiki/Barbarastollen https://de.wikipedia.org/wiki/Barbarastollen