The Bibliotheca Philosophica Hermetica, or the Ritman library, is one of Amsterdam most hidden but wonderful treasures. Offering a unique collection of manuscripts (focusing on first and early editions) from the hermetic tradition, the library has a collection in the thousands of volumes, prints, and engravings. Incredibly affordable at 5 euros for a day pass, spend the day browsing through antique books on alchemy and mysticism that you are not likely to see elsewhere. Watch out for their inconspicuous entrance.
At first I thought One was the West Church, but later I saw the West Church and realized that this is the library next to the church.
The library has a firm structure and is very beautiful. We took pictures here.