Whilst Wycombe Wanderers fans were tucked up in bed 40 miles away ahead of the big day on Saturday, thousands of Wearsiders had already got the party started in the capital, gathering in Trafalgar Square.
This isn't the first time the Black Cats have completed a 'Trafalgar Takeover', either.
Sunderland visited Wembley twice in the 2018/19 season for the Papa John's Trophy final and the League One play-off final, and both times gathered at London's famous landmark the night before.
Now, it's almost become a tradition.
This time around though, Sunderland fans were sent a friendly warning by London officials that drinking was prohibited around the monuments, and suggested they attended licensed premises, instead.
But nothing was going to stand in the way of the Mackems, and after a week of bad press for football fans, Sunderland's Trafalgar Square visit demonstrated the passion and good nature that does exist within followers of the sport.
And I got to witness that first-hand.
It really was a sea of red and white as people of all ages - babies in prams being pushed by their parents, kids on shoulders, groups of friends and even the elderly - began their celebrations on Friday afternoon.
Fans chatted away to police officers monitoring the scenes as the area was packed full of thousands of Black Cats belting songs at the top of their lungs.
I've followed football my whole life, but this was like nothing I'd ever seen before.
People climbed the fountains, danced in the water, bright red flares were set off and fireworks even made an appearance. It really felt as if the whole of Sunderland was packed into one area, just under 300 miles away from home.
People passing by the commotion stopped were even stopping to take pictures of the electric scenes.
And despite having one of the most important games in the club's history the following day, fans stayed out until the small hours of the morning, soaking it all in.
The excitement and belief that this is their year to get out of England's third tier was infectious, and although they've been in League One for four seasons, Sunderland's support is as strong and passionate as ever.
And it's the incredibly dedicated fanbase that leads Sunderland legend and talkSPORT co-commentator Micky Gray to believe they more than deserve to be promoted on Saturday.
"We say it every season about how important it is to get back into the Championship, but you just look at that fan base," he told talkSPORT.com.
"In the semi-final with Sheffield Wednesday there was 44,000 supporters at the Stadium Of Light, it's just incredible.
"We shouldn't be anywhere near League One, but circumstances haven't gone our way and we've put ourselves in this situation."
He continued: "Different managers have had a try and I think everybody is keeping their fingers crossed that Alex Neil is the man to make it happen.
"A club like Sunderland probably shouldn't be anywhere near League One.
"The Championship and Premier League over the next 6-8 years is progression.
"You've got to start with the foundations, but you can't lay those foundations until you're in the Championship, so it's a huge game."
So, when Sunderland fans sing 'we're mental and we are mad' and 'we are the most loyal supporters the world has ever had', it really isn't just a song.
It really does carry meaning.
The football-loving city of Sunderland has been a sleeping giant for the last five years, but Friday night may have marked the beginning of their reawakening.
talkSPORT will have exclusive coverage from Wembley with kick-off set for 3pm.