If you want to advise a first time group of friends traveling to Barcelona in the last week of August about ONE thing that you consider is the best / most memorable thing you have seen / done in Barcelona, what would it be?
We have already done our schedule for the 5 days we will be in the city. But I was thinking of asking fellow travelers / city experts about the ONE BEST THING that crosses their mind when they think about Barcelona. It could be one of the big famous attractions, an event that only goes on during the last week of August or even a "hidden gem" that most tourists may not know about
So, if you would like to share your advice, that would be great.