A sea of red filled the square in Bordeaux to watch, and join in with, the performance.
Fans in France, Bordeaux, were treated to a surprise concert made up of choirs from across Wales on Sunday, ahead of the game against Fiji.
The 'flashmob' choir idea started out with a few choristers from Côr y Gleision but word soon spread meaning more than 80 singers from other choirs were involved. Members from the London Welsh Male Voice, Builth Wells Choir and many more made up the group.
The singing began with about 10 individuals but by the end, hundreds of Welsh voices filled the square in Bordeaux as other choir members and the crowd joined in.
The group performed songs like Bread of Heaven, Calon Lân, Yma o Hyd and the Welsh and French national anthems.
Gwilym Hughes, from Côr y Gleision, led the Bordeaux flash mob and described it as "amazing" and "quite emotional".
He said: "It was an amazing experience and a bit overwhelming seeing how many people joined in or came just to listen."
He explained that the idea came from a fellow singer at the Cardiff-based choir he belongs to.
"Huw Davies and myself from Côr y Gleision organised the event," he said.
"It was actually Huw's idea but as he was only joining us in Nice, he delegated to myself to organise the Bordeaux event.
"We both contacted lots of choirs around Wales and got a great response. I was still only expecting about 30 or so but by the morning of the event, more than 80 had asked to join the group.
"We met for the first time an hour before and had a short rehearsal by the river. By the time we arrived at Place de la Bourse, there was a crowd of onlookers that must have numbered hundreds.
He added: "It was a great feeling singing out to a sea of red and hearing everyone join in.
"A particularly special moment was singing the French anthem before of course 'Hen Wlad'."
The surprise concert took place ahead of the Wales v Fiji clash, which ended in a tense second half but ultimately saw Warren Gatland's side take a 32 - 26 victory.
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