I visited Barcelona for 2 days at the end of a cruise a few years ago. Take a little bus tour for about 4 hours, they will take you to see the sights such as the famous unfinished "church" Sagrada Familia and the shopping are Las Ramblas. We had dinner at a somewhat famous restaurant called Quatre Gats (4 cats), it was one of the best meals I've ever had. We also saw Flamenco dancing, but after the first 5 minutes it was pretty repetitive so up to you if that interests you. Have fun!