A 10-minute walk toward the river from the main campus of Warsaw University is the relatively new (1999) Warsaw University Library, a sight not to be missed, even if you're not on a research trip. You'll find some shops and cafés on the ground floor, but it's the building's roof and its rooftop garden that are truly special and definitely worth the trip. The garden, open to the general public, is both vast and intimate, not to mention one of the most beautiful rooftop spaces in all of Europe. With its nooks, crannies, brooks, paths, lawns, and benches where you can hide with or without a book, the garden provides a perfect space for thought and inspiration. It is also full of surprises: look for various "reinterpretations" of Einstein's theory of relativity. In addition, you'll find a kaleidoscope of vistas of both the city and the library's interior. If you dare, cross the footbridge over the glass library roof—with the sky reflected under your feet, you literally walk in the clouds.