We'll admit: libraries aren't normally the first place on our agenda when travelling internationally, but Book Mountain — also known by its native name Boekenberg Bibliotheek Spijkenisse — isn't a normal library. Designed by Rotterdam-based MVRDV, this stunning structure has already received multiple architectural awards, as the glass pyramid houses a huge structure of books spanning multiple floors, with an outer path to the top measuring 480 meters long and a cafĂ© with fantastic views perched at the top. Feel free to stop by any time, but if you want a more complete visit, the library hosts a free guided tour every Thursday at 2:30 p.m.