Appreciate the quiet environment at Deutsches Literaturarchiv while browsing through the books, journals and newspapers. See if you can find some board games too.
This collection of books is in Marbach am Neckar, a destination that has lots going for it! Ludwigsburg Palace, Monrepos Lakeside Palace, and Blooming Baroque are other good sightseeing opportunities nearby when you've finished up at Deutsches Literaturarchiv.