September in Barcelona: La Mercè, the Festival That Transforms the City

September is one of the most special months to enjoy Barcelona. Temperatures become more pleasant, and the city prepares for one of the most anticipated events of the year: La Mercè, Barcelona’s main festival, which in 2026 will take place from September 23 to 27.

During these days, Barcelona celebrates its patron saint with a programme that combines tradition, culture and contemporary events. Streets, squares and some of the city’s most iconic spaces are transformed into open-air stages.

Among the most representative traditions are the castellers, impressive human towers that can rise to remarkable heights. Building a castell requires balance, coordination and the collective effort of dozens of people. Watching these human structures take shape in the middle of a square, until the youngest member reaches the top, is one of the most exciting moments of La Mercè and a true symbol of Catalan culture.

Another unique event is the correfoc, a traditional spectacle in which groups dressed as devils parade through the streets surrounded by fire, sparks, music and drums, creating an unforgettable atmosphere. These traditions are complemented by concerts, cultural activities and performances across Barcelona.

La Mercè is the perfect opportunity to rediscover the city, explore its neighbourhoods and enjoy its architecture in a different atmosphere. For those visiting Barcelona in September, it offers a unique way to experience the local culture and one of the city’s most emblematic celebrations.