Graphically it should suggest the experience of wandering the stacks of a large library. Have you been in the stacks of a big University or city library? Narrow, ill-lit aisles, books shelved on both sides, from the floor to well above your head. Oooh! Oooh! you could model it after Terry Pratchett's Unseen University Library[1].

[1] https://wiki.lspace.org/mediawiki/Library