The last time they made it to this tournament was way back in 1958. As a country, Wales has endured the heartache of so many near misses since then. But in June a 1-0 home win over Ukraine ended their decades-long quest for qualification, and tonight their eagerly awaited World Cup campaign finally begins.
They’ll have to wait just a little bit longer though, until 10pm local time (7pm UK time) to get going against their first opponents, the USA.
Wales’ talisman and record goal scorer, Gareth Bale, is a five times Champions League winner and has led his team to two European Championships, but has never played in a World Cup tournament.
We now know that the team he leads out tonight won’t include midfielder Joe Allen. Allen has been an important player for Wales and was part of the squad that propelled them to the semi-finals of Euro 2016.
He’s not played since mid-September because of a hamstring injury, but Wales’ manager Rob Page said yesterday that he hoped that resting Allen today would give him a chance of being fit for Wales’ second group game against Iran.
That match will kick off on Friday, at 10am UK time. Recognising the huge national significance of this moment, the Welsh government has given schools permission to suspend classes and allow children to watch the game instead.
And that leaves one final - potentially crucial - group match which will see Wales come up against England on 29th November.
Thousands of England and Wales fans have travelled to Qatar for the opening games, and millions more will be cheering the teams on from home.
Wales fans are easy to spot because of the red, yellow and green bucket hats that have become part of their uniform over the past few years, and the big smiles on their faces.
Wales are not the favourites to win their group - but in many ways they have nothing to lose. They have already made their country proud by achieving a feat no other Welsh side has managed since 1958.
At a press conference in Doha yesterday, Bale said: "It's probably the biggest honour we could have for our country to qualify for a World Cup, something we have not done for 64 years.
"Schools are going to stop to watch our games. It's one of those moments which is a massive piece of history, something we have wanted.
"We have the support of the nation back home, no matter what happens. As long as we give 100 per cent our country will love us for that."
He spoke about the most important thing being to grow football in Wales, and to inspire another generation. Before they even kick a ball tonight, the Wales team can cross that one off their list because, just by being here, they have already done that.
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