When planning a trip to Barcelona, and Spain in general, make sure to pack your most comfortable pair of shoes. Walking all day is not only for the pilgrims anymore and Europe is well-known to leave one feet-up with a glass of wine at the end of a day out and about. But more to the point: bring shoes you can take to the mountain!
If you’re looking to escape the urban jungle after a few days (or just 1) I recommend a day trip to Montserrat to clear your mind and breathe in that freshness. Big, round peaks, lots of trees in the valleys, picnic spots… Nature. I treat myself to this getaway every couple of weeks.