If you should be in Oxford up to the 27th. of October, and you have time to take in a small exhibition, then do visit Magical Books at the Bodleian Library.
The website to which I've linked there gives a comprehensive summary of themes and images of many of the exhibits, but among them are Shakespeare's First Folio, a dinner plate which inspired Alan Garner's The Owl Service, C.S. Lewis's map of Narnia, and an alethiometer commissioned by Philip Pullman and based on that which Lyra reads in His Dark Materials. Papers belonging to the 'Oxford School' of fantasy writers, i.e. Tolkien, Lewis, Garner, Susan Cooper, and Pullman are on display next to many very ancient books from the library's collection in which appear the myths and legends on which the modern authors have drawn for their own work.