If you're craving some intellectual stimulation, make sure you check out MUHBA El Call. Whether it's history, culture or traditions, you'll find plenty of thought-provoking displays to keep your mind active here.
This Downtown Barcelona collection of historical artifacts is a good place to start your day of sightseeing. There's plenty to see and do in the vicinity, like Sagrada Familia, La Rambla, and Plaça de Catalunya. Take your time at MUHBA El Call before hitting up these other fine sights.