As part of her 76th birthday celebrations on April 16, Queen Margrethe II, the first female monarch of Denmark since 1412, appeared on the palace balcony in Copenhagen to acknowledge the cheers from a happy thong of subjects gathered below.
And it's a carefully choreographed affair. Queen Margrethe, who stunned in blue, was accompanied by husband Prince Henrick and a succession of her children and grandchildren.
But it’s what the Danish queen did next that may come as a surprise.
A video displayed on the Danish monarchy's revamped website shows Queen Margrethe leading the crowd in a mass chant (beginning around 0:33 seconds).
"She's calling for everyone to join her in nine hurrahs for Denmark," a Danish diplomatic source tells PEOPLE. "It's a toast to Denmark."
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"It's a traditional Danish custom – not among everybody – but if, say, you went to a wedding anniversary, someone might say, 'Let's all call out ninefold for the couple.’ "
But why nine times? The custom's origins seem to have become lost over the years.
And when it comes to Queen Elizabeth’s upcoming 90th birthday celebrations, don’t expect to see her leading a cheer on the balcony of Buckingham Palace – the British monarchy doesn’t embrace cheerleading with quite the same enthusiasm as their Danish counterparts!