Pleasant and surprising, the carefully-tended gardens on the roof of Warsaw University's library are free to the public and offer some great views of Warsaw.
Warsaw University's Library Gardens - Why They're Worth Seeing
This free Warsaw attraction makes an interesting excursion for nature lovers, photographers, or those who just need to escape the bustle of the city. The gardens, planted on the roof of the library, either hide or work with the roof's existing structures - like air vents - to create a bio-industrial, floating landscape. Foot bridges, hidden nooks, and arch-covered pathways form the perfect spot in which to read a book, eat a picnic lunch, or steal some kisses from a date.
Warsaw University's Library Gardens - How to Get There

Warsaw University Library Exterior
Kerry Kubilius, licensed to About.comWarsaw University is located on the Royal Route, and is easily identified by the crowds of students entering and exiting the campus under the iron scrollwork university sign. Once inside the campus, you'll see a map located on your immediate left. Use this to get your bearings, then begin walking in the general direction towards the river.
The library is housed in a building of glass and oxidized metal that announces in large, bold letters "Biblioteka Uniwersytecka." To the left of the building, you'll see both the entrance to the library and the entrance to the gardens. You can explore the lobby of the library or continue on straight to the gardens.
Warsaw University Library - Stacks and Dining
While it's possible to enter the library itself, you'll have to check your coat. Tours are also available. If you're hungry, it's also possible to get a snack at one of the cafes located off the library lobby. The rather upscale restaurant, Biblioteka, is best if you don't mind spending quite a bit more than a student's lunch budget and your taste buds require more than a coffee and a roll.
Warsaw University's Library - Other Information

Warsaw University Library Students
Kerry Kubilius, licensed to About.com