I visited Barcelona years ago on my first trip to Europe, and looking back I have no real idea what I did while there besides seemingly over enjoying the tapas and sangria. I wandered with no real knowledge of the sights, but still managed to have an incredible time. The main tourist experience I had back then was watching (also dancing and singing along on the edge of) the Magic Fountain of Montjuïc which I highly recommend to anyone visiting during the summer nights.
First thing on my list this time in Barcelona was Catalan architect Antoni Gaudí’s magnificent Park Güell. I adore Gaudí’s work, and unlike his scattered buildings throughout Barcelona, the garden complex of Park Güell is a whole site including the home where Gaudí moved in with his family. After wandering the sea serpent terrace I visited Gaudí’s house that Count Eusebi Güell built, “la Torre Rosa,” containing furniture that Gaudí designed including my favourite chandeliers. The park was incredible and also incredibly hard to move around in, with thousands of tourists snapping away at every mosaic tile (myself included). To enter the Park is free but I highly suggest coming first thing in the morning.