The Belgian festival Tomorrowland, one of the largest electronic music events in the world, opened as scheduled despite concerns following a fire that destroyed its main stage.

Organizers announced that an “alternative structure” had been built in its place, replacing the “beloved main stage” that was engulfed in flames on Wednesday. The cause of the fire remains unknown.

“Our teams are working around the clock, with all their heart and soul, to turn the impossible into reality. Tomorrowland will unite, stronger than ever!” read the official statement from the organizers.

Footage from local television showed hundreds of attendees entering the festival grounds in the town of Boom, near Antwerp, as early as the afternoon. Around 400,000 people are expected to attend over the two festival weekends. Among the dozens of performers are names like David Guetta, Lost Frequencies, and Charlotte de Witte.

Footage of the fire shared on social media showed flames consuming the elaborate stage design, which depicted a frozen fairytale realm with a giant ice lion, castles, and snowy peaks.

The new main stage — smaller in size — was erected in less than 48 hours. After fire services and police confirmed it was safe, it opened at 4:00 p.m. local time, two hours after the festival’s other 15 stages.

“This is a new concept — artists will be much closer to the audience, in a more intimate atmosphere,” said event spokesperson Debbie Wilmsen to the media.

Tomorrowland was founded 20 years ago by two Flemish brothers in a country that gave birth to the genre. In October, the festival will be held in Brazil, while its winter edition is organized annually in the ski resort of Alpe d’Huez in France.