Whoever said science was boring and only for geeks has obviously never set foot in Cosmocaixa. This newly refurbished modern museum, situated in the Sant Gervasi neighbourhood, offers its visitors the chance to learn and understand the most complicated mysteries of science with the simplest of means: experience it for yourself. The most amazing exhibit is the 'Flooded Forest', the Amazonian rainforest exhibit. An very fun way to spend very little cash (general admission is free but if you want to touch animals or visit specialty exhibits, there is a small fee) and an informative afternoon.