As usual, the façade of the Ajuntament will be transformed, this year by a spectactular 3D mapping display, whose theme this year is a the pioneers of early cinema, featuring George Meliès, brought to you by Franc Aleu.
Throughout the five-day celebration, the city will play host to 106 concerts. On this first day, some of the highlights will include Manos de Topo (Plaça Reial, 11pm), Sanjosex & Chicuelo (Av de la Catedral, 12.30am) and the concerts in the Fòrum by Miss Caffeina (10.30pm), Supersubmarina (1.30am) and Dorian (3am).
The Parc de la Ciutadella have a double function as the setting for a historical re-creation of 1714 Barcelona (when the battle for Barcelona came to an end), and it will be the epicentre for the Performing Arts. Today you can check out the robot UFO MC14 (9pm-1.30am), dance from Kulbik Dance (10.30pm) or a bit of Combinat 47 of the Ateneu Popular Nou Barris (10pm). This year sees the 20th anniversary of MercèDansa, which is reviving traditional dance. Don't miss your chance to see them up-close in Plaça Sant Jaume (11am-6pm). You'll be able to see some of the most traditional activities of the festival today, including the falcon parade as well as a procession of fire-breathing dragons and other beasts that will set out from Plaça Sant Jaume at 9pm.
At 11pm you can check out Mambo Jambo who will be filling Plaça Catalunya with their sound and rhythm. As part of the BAM music festival in the Antiga Fàbrica Damm, dance around with The Free Fall Band (6.30pm) and Miles Kanes (9.30pm).
Once again Montjuïc Castle becomes a circus on the 21st, 22nd and 24th with nearly 20 companies from around the globe, featuring a combination of top international circus performances on stage 1 Fossat de Santa Eulàlia.
Parc de la Ciutadella plays host to Dei Furbi's Magic Flute (4.30pm & 8pm), Hotot, Marcel Tomàs (1.30pm) and electronica versions of operas (from 4pm), seeing as Vienna is the special guest of La Mercè this year.
Nighttime is all about oohing and ahhing over fireworks shows, with good music, amazing colours, and the smell of gunpowder. Tonight pyrotechnic greats the Caballer brothers are at the helm. Get down to Barceloneta near the Gas breakwater to see the show in all its splendor (10pm). Sunday is another big day for traditional peformances: ball de bastons (a type of dance incorporating bamboo sticks or canes) (Plaça Sant Jaume, 10am); a competition of the traditional Catalan dance, the sardana (Av de la Catedral, 11am); the festa castellera (Plaça Sant Jaume, noon); and the big event, the Correfoc (Plaça de Antoni Maura, 8.30pm).
Today will also see a wide variety on the music side. Local musicans Pau Vallvé (9.15pm) and Standstill (10.45pm) will perform in the Plaça dels Àngels. Dani Nel·lo and the Barcelona Big Blues Band will play in the Palauet Albéniz (8pm), which opens its doors for free for the occasion. If you're more into top 40 and the like, head over to the space in Av de Maria Cristina, where there will be more pop sounds.
Sundays are when everyone's at the Piknic Electrònic, and this Mercè Sunday is no exception. This week admission to the Joan Brossa gardens are free, so you can take the whole family if the mood strikes (1pm-10pm).
In charge of lighting up the sky tonight are Russian pyrotechnicians Bolshoy Prazdnik (Gas breakwater, 10pm) who will show off their own tradition of fireworks displays. If you missed it on Friday, you have a second chance to see the historical re-creation of 1714 Barcelona in the Parc de la Ciutadella, where you'll also be able to enjoy some great Performing Arts shows. And don't forget to take the kids to Montjuïc Castle for the loads of circus acts going on there (suitable for adults as well). And now it's time for some classical music with the Orquestra Simfònica de Barcelona i Nacional de Catalunya, more popularly known (for obvious reasons) as the OBC (Av de la Catedral, 10pm). And if you didn't get enough outdoor cinema this summer and you want to brush up on your Spanish, head to Plaça de la Mercè, where they'll be showing the Goya-award-nominated cops-against-drug-traffickers film 'Grupo 7' ('Unit 7') (10pm).
Music from the BAM festival rings out of Plaça Catalunya and other squares nearby, but you can also check out the poppier side of things at the Av Maria Cristina venue, starting from 7.15pm to 1am.
Over at the Museu Marítim, at 9pm, there's a Xambanga de Gegants, a procession of the giants dressed in costumes, which will end up in Plaça Sant Jaume, where they'll spend the night. The actual day of the patron saint has arrived, so you'll find that while lots of shops are closed around town, there's still loads going on. The most traditional of all the events take place this morning: morning of the 'grallers' (playing the traditional reed instrument that accompanies the sardana) (Plaça de la Mercè. 8 h); trabucaires (display of 'trabuco' guns) (Av de la Catedral, 9.45am); gegants & capgrossos (Plaça Sant Jaume, 11am); and casteller shows (12.30pm). In the afternoon be on the lookout for the Mercè parade that starts out in Marquès de l'Argentera (6pm) and finishes up in Plaça Sant Jaume.
The best of the circus performances are still to come in the last hours at the Montjuïc Castle, as are the Performance Arts in the Parc de la Ciutadella.
But undoubtedly the most anticipated event is the Piromusical de la Mercè (10pm) which marks the official end of the city's biggest festival, and it does so in big, loud style. This year's fireworks and music show will of course include nods to music from special guest city Vienna as well as to the tricentennial of the siege of Barcelona, but you'll also be treated to Catalana pop and rock songs as well as contemporary symphonic compositions.
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