Suggest Your Favorite Book For My Solo Euro-Trip!

Hello!

I will be in Europe for a few weeks from late November to early December. I plan on spending a fair bit of that time reading at parks, coffee shops, by rivers, and canals, etc. Please suggest your gut-reaction "favorite" book, something that was a joy to read! I am open to all genres and topics, but would like to perhaps stay away from very heavy non-fiction that provoke overwhelming or negative feelings. :) Thank you!