For literary trips, here's the honest sort by depth.
Tier 1 — destinations on their own
- Paris: Hemingway, Joyce, Beauvoir, Camus, Proust. Shakespeare and Company bookshop. Saint-Germain café trail.
- London: Dickens, Woolf, Conan Doyle, Orwell. Bloomsbury group walks. British Library.
- Dublin: Joyce (Bloomsday June 16), Yeats, Beckett, Wilde. Dublin Writers Museum.
- Prague: Kafka. The Old Jewish Cemetery, Kafka Museum, Café Louvre.
- Lisbon: Pessoa. Casa Fernando Pessoa, A Brasileira café.
Tier 2 — strong literary cities
- Edinburgh: Walter Scott, Robert Louis Stevenson, J.K. Rowling.
- St. Petersburg (politics aside): Dostoevsky, Pushkin, Akhmatova.
- Trieste, Italy: Joyce wrote much of Ulysses here. Saba, Svevo.
- Hamburg, Berlin: Mann, Brecht, Döblin.
- Vienna: Schnitzler, Zweig, Roth. Café Central was Trotsky's office.
Tier 3 — niche but rewarding
- Heidelberg: German Romantic poets.
- Salzburg: Mozart but also Stefan Zweig.
- Florence: Dante, Boccaccio.
- Stratford-upon-Avon: Shakespeare obviously.
- Stockholm: Strindberg, Lagerlöf.
Strategy
Plan around specific writer's home/museum hours. Many small literary museums are closed Mondays. Combine with their café-of-residence and a long lunch with the relevant book.