The 333 Bulgarian folk musicians gathered in central Sofia late on Wednesday, blowing their kaba-gaidas - bagpipes from the Rhodope mountains in the south of the Balkan country - to set the first such Guinness world record.

Dressed in traditional colourful Rhodope costumes, bagpipers started with a famous folk song - Delyu Haidutin - which was included in a Voyager golden record with the songs and sounds of our planet and sent as a message to space by NASA in 1977.

The event also aimed to bring a spot of joy to a nation which a survey showed was among the most unhappy on the planet. Having joined the European Union in 2007, it is still the bloc's poorest member and recovering from a deep recession.

"You have big roots. Do not lose them, but increase old tradition and culture," Shankar told an audience of over 4,000 people who gathered to hear his advice on how to be happy and listen to the bagpipers.

According to the Earth Institute's World Happiness Report released in April, Bulgaria was in the top 10 of more than 150 countries which were least satisfied with life and was the most unhappy in Europe.

To help came Indian guru Ravi Shankar - one of the world's most popular spiritual leaders who travels around the world to spread his vision of a stress-free, violence-free society.

His The Art of Living foundation is the world's biggest non-governmental organisation, and 30 million people in 155 countries have attended Shankar's courses.

(Reporting by Tsvetelia Tsolova, editing by Paul Casciato)

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