I recently went to Barcelona to visit my sister for her birthday. She has lived there for about 9 years now and I usually visit at least once a year, it's such an amazing city. I only went for a long weekend and as I've mostly done all the touristy things now we spent most of our time on the beach!
Our favourite thing to do is to take the train up the coast to St Pol de Mar and visit the amazing restaurant right on the beach front and eat so much Paella and drink Sangria, heaven! It's only about 45 minutes from the city but it feels like another world, so relaxing with incredibly clear seas. You can walk along the coast from St Pol to the nearby town of Caella which takes you along the cliff tops and the views are just beautiful. There are also a few naturist beaches along they way if that floats your boat!