Lithuania's capital was flooded with pink food, decor, and colourful outfits on Saturday, as residents celebrated the Baltic nation's love for a cold beetroot dish commonly known as "pink soup".

While beetroot soup is beloved in many eastern European nations, Lithuania lays claim to Saltibarsciai -- made of kefir, cucumbers, beetroot, and dill -- eaten cold and a favourite on a hot summer's day.

"It's not just soup – it's a way of life," said the city's tourism agency Go Vilnius, which organised the first-ever festival in its honour.

French student Victor Delcroix came dressed as a bowl of "Pink Soup."

"I fell in love with Saltibarsciai and I felt obliged to wear this to honour it," he said before jumping on a giant pink slip-and-slide covered in foam.

Elsewhere some festival-goers prepared to set a record with the largest-ever bowl of Saltibarsciai.

Topped with sour cream and boiled eggs and served with boiled or fried potatoes, "pink soup" is a summer staple in Lithuania.

"There are bars ... that prepare them in interesting ways, like a sushi place that makes it with wasabi," said Ricardas Andrijauskas, at the festival.

"We usually make it more traditionally."

He was not entirely convinced by all the innovations, he confessed. "Not with wasabi," he said, shaking his head.

- 'Instagrammable' soup -

Elsewhere at the festival vendors were selling pink ice-cream, coffee, cocktails and perfumes.

Go Vilnius wants the soup to boost food tourism to the city.

"Our city's gastro scene has skyrocketed in the past years," Inga Romanovskienė, director of Go Vilnius, told AFP. 

"Historical cuisine recipes from the 700 years of the capital's multicultural heritage, which celebrate a unique local fusion of Lithuanian, Jewish, Polish cuisine, have also settled in the menus of the city's restaurants."

According to Lithuanians, the dish originated in the Grand Duchy of Lithuania, which existed until 1795 and included swathes of territory in present-day Belarus, Russia and Ukraine.

However, Poland and Belarus are among those who contest its heritage.

Pink soup has also become a star on social media.

"It's called one of the most 'instagrammable' soups," said Dovile Seliuke, spokeswoman of the country's tourism promotion agency, Travel Lithuania.

The Pink Soup Fest is taking place against the backdrop of hundreds of Ukrainian flags fluttering around the capital. 

Over 80,000 Ukrainians have now sought asylum in Lithuania, a Baltic country of 2.7 million people. 

"The celebration helps take your mind off [...] the war in Ukraine," said Rasa Kasitiene, who with her daughter was dressed up all in pink. 

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