Barcelona's Font Magica is by far the best free event I have ever had the pleasure of experiencing - it is simply spectacular. Buy a bottle of wine or a couple of beers, some snacks, pack a blanket if it’s cool, and head to Montjuic to enjoy the fountains lit up like fire and dancing to the music. It may sound a little cheesy, but it’s amazing! From October to April it comes alive on Fridays and Saturdays from 7:00 pm to 9:00 pm and in the summer (May to September) it’s packed with spectators for the Thursday, Friday, Saturday and Sunday shows from 9:00 pm to 11:30 pm. And it’s all free!
Nearest Metro -Placa Espanya.
http:bcn.es/fonts