Käärijä (Jere Pöyhönen) and British-Norwegian DJ Alan Walker performed on a tram in downtown Helsinki on Wednesday evening.
The appearance also featured the premiere of Walker's new remix of Käärijä's track Cha Cha Cha. The original version of that song helped Finland place second in this year's Eurovision Song Contest.
Both artists posted photos and video clips of the engagement, which showed the streetcar filled with enthusiastic fans.
The event was organised by commercial radio station NRJ.
Käärijä fan Kati Ruotsalainen won a ticket for the tram gig in a drawing on Wednesday.
"There was an incredibly great feeling on the tram. The mood was great," she explained.
The tram departed from the city's Market Square and clacked along tracks around town.
"But I didn't have a chance to look around at the scenery," Ruotsalainen noted.
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