Three orchestras will gather in Montreal next summer for a massive concert to celebrate the city’s 375th birthday.

Montreal Symphonique, a concept show created and produced by GSI Music, will bring Montreal’s Symphony Orchestra, Metropolitan Orchestra, and the McGill Symphony Orchestra together for the first time in a free, live concert, showcasing over 300 local musicians from an outdoor venue.

“One of our greatest signatures is our music — our music and our creativity” Montreal Mayor Denis Coderre said in a press conference Monday. “By having these three orchestras — a first, this is a unique even t— 375 musicians will together show their love for classical music, but also for one of the greatest metropolises in the world.”

The concert will also feature performances by popular local singers, though specific names have not yet been unveiled by the event’s organizers.

Nicolas Lemieux, president of GSI Music, explained that the outdoor staging will keep the musical rendez-vous both unique and accessible, while showcasing local colour and cultural diversity.

The show will adhere to the theme of “seasons,” organizers said, and will make reference to several of the aspects that personify Montreal, including its habitants, landmarks, and the overall rhythm of city life.

More implicitly, organizers said that there will be focus on a fifth, “creative” season, as an invitation to the public to join together and shape the city’s future.

Montreal Symphonique will officially crescendo on August 19, 2017.