When describing his musical vision, United Flavour producer, founder and bassist Djei likes to quote a lyric from reggae masters Black Uhuru: "The whole world is Africa, but it has been divided into separate states."

United Flavour's urban sound, with its solid R&B, reggae and hip-hop foundations, is angling to be as big in 21st-century Prague as polkas and Mozart's operas were during their times. The reasons are many, but the most obvious is simple, as Djei observes: "In Prague [today], you can have all the world in one café."

So perhaps it's fitting that United Flavour is headlining a gritty lineup as part of the summer's most unlikely music event, a combination dance concert and whitewater kayaking competition. Sponsored by the Czech National Association of Wild Water Rodeo (CNAWR), the three-day Prague Whitewater Rodeo 2005 is the concluding round of the Euro Cup competition. Saturday night, the semifinals on the water alternate with a music program on the banks of the Vltava in what should be a memorable spectacle.

United Flavour itself features an international mix, with five nationalities represented by band members whose influences transcend national borders. Djei's family migrated from the Ivory Coast to the African-Magreb-Arabic suburbs of Paris, where rai and reggae were as audible on the street as hip-hop, R&B and rock music. Vocalist and songwriter Carmen Morejón's origins are from the south of Spain. Her earlier life in Badajoz and Seville brings a natural array of influences from southern Iberia, as well as the Latino new-world variations of Hispanic urban music. Catalan Jose Ramon's keyboards echo that region's penchant for nuance, with a distinct Barcelona edge. Keyboard player Split from Bratislava brings a rock sensibility informed by an earlier interest in gospel music to the group. And Jaro and Standa from the Czech Republic deliver their enthusiastic finesse on drums and percussion, respectively.

Favorite guest artists who record and perform with the band include Zambian rapper Henry D (aka Bigg Dawg), who also brings his smooth hip-hop delivery to his own projects D Style and Forbidden Fruit.

And maybe Djei's ambitions aren't as far removed from Prague's musical traditions as they might seem. "You can take some [polka-based] Czech traditional music, give the drum beat a little deeper sound, take the horns and give that a guitar and piano sound, and you have ska right there."

As it happens, the Prague ska group Skapollo is opening the Saturday night festivities at 6 p.m. Then the kayaking semifinals take center stage. At 9:30, DJ Admiral Kolibal starts spinning crucial beats to get the audience up on its feet, possibly with Henry D joining in. United Flavour is scheduled to play at 10 p.m.

For those still ready to dance past the midnight hour, Jamaican emcee Mr. Mention will take the stage. Mr. Mention is a singing DJ who will be working reggae, dancehall and blues influences along with Riddimshot vocalist Charmeen. Backing Mr. Mention and Charmeen will be reggae pioneers B. Rokka and Admiral Kolibal, spinning vinyl from their archives of reggae and dancehall tracks.