Rosalía's new song and castellers: Barcelona caps off La Mercè festivities

Barcelona's La Mercè festival is over for another year, but not before going out with a bang.

As ever, a fireworks show set to music brought the curtains down on another spectacular festival of music, arts, and folk culture, and this time with a special guest appearance. 

To celebrate her 32nd birthday on Wednesday, superstar singer Rosalía was invited to select the music for the 'piromusical' - the "pyrotechnic musical" that traditionally finishes off La Mercè at the Magic Fountain on Avinguda Maria Cristina. 

Rosalía premiered her latest track at the event, 'Omega', a collaboration with Ralphie Choo.

Her setlist also brought the 100,000 visitors to the fireworks show through a selection of dancehall, RnB, indie, pop, and ballads, with tracks from Vybz Kartel, Arctic Monkeys, The Strokes, Caroline Polachek, Elvis, and more.

Human towers

Earlier on Tuesday, Plaça Sant Jaume was the scene of a traditional 'castellers' human towers meet up. 

Thousands packed into the city center square to watch the traditional human towers display done in an old fashioned way, meaning the eight groups had two hours to construct 30 towers.

The Castellers de Sants gang stood out with a tower standing 9 people high, unleashing euphoria among spectators gathered. 

Other gangs all completed towers of 7 or 8 people. Earlier in the morning, giants and beasts performed their traditional showy dances.