1. Strahov Library
What is it? The library of the Premonstratensian monastery built from 1671 at Strahov, which contains around 200,000 books across its two halls (one theological, one classicist). It also has some seriously nice ceilings, designed by Anton Maulbertsch and Siard Nosecký.
Why go? If you’ve ever thought libraries were boring, this will change your mind. The two halls at Strahov frequently appear on lists of the most beautiful libraries in the world, and for very good reason.