Inside the Puratos bakery in St. Vith, Belgium, is a carefully curated library of sourdough starters. Its librarian, Karl De Smedt, watches over now 84 distinct sourdough starters. He and his staff carefully tend to the living collection by refreshing the doughs every two months according to their original recipes. Some of those doughs are over a hundred years old.
You can take a virtual tour of the library here.
-via Atlas Obscura