Watch: So, what was it REALLY like to be an Irish fan in Paris last night?
From early evening they started arriving on metros, in taxis and on foot.
Word had quickly spread around social media and through bar whispers that the party was happening in Montmartre.
Fans dropped their plans to visit Paris' cultural landmarks and flocked to Boulevard de Clichy.
By 9pm close to 2,000 had gathered on the street outside the Moulin Rouge – two hours later and that number had more than doubled.
Brothers Paul (34) and Vinny Dooley (39) got a taxi there after a local barman told them of the party.
Vinny said: “It was bumper to bumper. From about a mile out you could see this crowd hopping on top of the middle of the fountain and on top of each others' heads.
“We just jumped out of the taxi then and just ran up and embraced the madness”
Paul added: “It was just unbelievable. There was loads of Swedish there, loads of Croatians, all of us having the craic.”
Police closed off the street to allow the heaving crowd some space to breathe, not that anyone actually wanted it.
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Fans stood up and sat down more times than at a Good Friday mass but this time they were worshipping at the altar of the Boys in Green.
More fans started filtering in on the Metro and in taxis. One group even got their cab driver to play the Wolfe Tones' 'Sean South of Garryowen' from the radio – triggering a rousing rendition of the ballad from the larger crowd.
Aubrey McMahon (18) from Celbridge, Co Kildare went to the French Champion Hurdle day in Auteuil before taking a taxi straight up to the strip.
He said: “Straight into the pub, a few pints and out onto the street. There was just cans flying everywhere.
“You could feel the buzz around the place at all times. I've never seen anything like that before, not even at Cheltenham,” explained the former amateur jockey.
From 11pm the place reached "full Italia '90 levels" with fans climbing on top of public toilets. Conor Falvey (33) from Killorglin even scaled a tree.
Moments later one man, who asked not to be named, tried the same trick but it ended badly when he fell 10 feet onto the pavement.
Fans were quick to gather around him to see if he was okay. In the absence of proper first aid equipment supporters offered him sips of beer out of their cans.
He later later told Independent.ie: “I'm okay now but I'll probably feel that in the morning.”
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The largest game of keepy-up was ongoing throughout the night. It only ending when someone kicked the ball so high that it hit off the iconic Moulin Rouge windmill and landed on the roof of the building – sparking a wave of groans.
Later it was replaced by a giant inflated sex toy.
Gardaí, who are based in Paris, received no reports of incidents and police who were on the street did not interrupt the party. Some even posed for pictures with fans – sparking chants of “get your guns out for the lads”.
At least one Irish fan was taken away in an ambulance.
Most of the bars were too busy to secure a pint so many stocked up on cans from the nearby supermarchés. Some entrepreneurial locals walked up and down the streets selling cans for the inflated price of €4 each.
As 2am hit thoughts moved from partying to food. But like any good Irish party it didn't end until the national anthem was sung.
And so, with arms around each other, up to 3,000 mostly male fans belted out Amhrán na Bfhiann together.
Diarmuid Aherne (32) from Knocklyon in Dublin said: “Police came along and everyone just kind of evaporated. I think food was on everyone's mind at that stage.”
Thoughts are now turning to tonight and the potential party that could break out if we beat the Swedes.
Paul Dooley said: “If we win then you can just close Paris, that will be it.”