Hands down my favorite spot in Warsaw. Rent a bike from any of the stations and ride along the…read moreriver until you hit the University library. Head straight for the roof and you won't be disappointed. It is a fairytale land situated in the middle of Warsaw with hanging baskets where you can lay, tons of grass to sit on, and lots of garden space on the roof to walk around and sit on. You get a great view of the Warsaw skyline and on the other side, you can admire the river.