About 2,500 people are expected to take part a Celtic festival - in the Czech Republic.
In recent years the rediscovery of Central Europe's Celtic heritage has become increasingly popular.
Central Europe was settled by Celts until around 500 AD but they were replaced by later waves of Germanic and Slavic tribes.
Celts arrived in Central Europe 2,500 years ago
Around a dozen groups are performing as the festival of Beltine or Beltane, is celebrated in the southern town of Telc.
The bands - including one called Czeltic, spelt with a "z" - are not from Ireland, Scotland, Wales or even Brittany. They are Czechs who are reclaiming their Celtic heritage.
Celtic tribes first settled in Central Europe 2,500 years ago, but little remains except some place names and archaeological sites.
Nonetheless, since the end of communism in 1989 there has been a steady growth of interest in Celtic culture.
Partly it is to do with getting away from the Slavic links emphasised by the Russians, and partly about having fun and the international success of shows like Riverdance.
But Ireland in particular is a model for the Czechs as they prepare to join the European Union.
They have seen Ireland's economic transformation.
They will be hoping to imitate more than a few dance steps when they join the EU next year.