I find it awe inspiring to be able to see one of the most important documents in UK history and world history. A translation of the medieval English is on the outside of the booth the Magna Carta is kept in (to shield it from direct light, no photos are allowed either, though you can take pictures of the Chapter House in which it is kept. See below).
This led me to think about what documents might be important in your fictional world. Would it be an original spell book, the classic fairy tales or other traditional magical work? Can anyone see/have access to these? Who wrote them? What triggered the writing of them?