(CNN) -- Gareth Bale, Sam Warburton and now Geraint Thomas. Three sporting greats, Welshmen who have created history and, astonishingly, world stars who went to the same school.

The exploits of Thomas, who Sunday became the first Welshman and only the third Briton to win the Tour de France, has put the spotlight firmly on the Welsh state school with a reputation for breeding champions.

"It should be written into a Hollywood film," says Huw Jones-Williams, headteacher of Whitchurch High in Cardiff.

Thomas -- also a double Olympic gold medalist and a Commonwealth champion -- joins Real Madrid star Bale, once the world's most expensive footballer, and former Wales and Lions rugby union captain Warburton, in the school's celebrated sporting trinity.

Warburton and Bale, both 29, were in the same year, while the 32-year-old Thomas was three years above.

Is there something in the water? Not quite, says Jones-Williams.

"It's almost a fairytale," Jones-Williams, who was deputy head when the trio were pupils, tells CNN World Sport.

"Just one would be incredible, two would be the most amazing coincidence, three? Somebody up there is looking down on us with the most amazing blessing. It's absolutely unreal. It should be written into a Hollywood film because it feels of that stature.

"I've not heard of anyone at any school with a similar thing, and particularly major sports. I'm not sure it will ever be repeated. It's certainly once in a lifetime. You can't believe what has happened with those three sports superstars."

Both Bale and Warburton were quick to congratulate Thomas, who could be set for a homecoming parade in the Welsh capital after winning cycling's most prestigious race.

"Incredible achievement from a fellow Whitchurch High pupil," tweeted Bale, a four-time Champions League winner, while the recently retired Warburton tweeted: "Absolutely awesome @GeraintThomas86! Thoroughly deserved, and couldn't happen to a nicer guy #legend"

It has been quite the summer for all three stars.

Not only has Thomas succeeded in a Grand Tour for the first time, but Bale scored twice in a man-of-the-match performance in the Champions League final in May. Earlier this month Warburton, who captained Wales a record 49 times and led the British and Irish Lions on two tours, announced his shock retirement from rugby.

'Make sure students dream big'

With 2,300 pupils, Whitchurch is one of the biggest comprehensive schools in the United Kingdom.

The celebrated trio are the standout faces in the school's "Wall of Fame," which helps inspire pupils, says Jones-Williams.

The wall includes a signed Real Madrid jersey from Bale, a Wales grand slam shirt worn by Warburton and a signed photo of Thomas.

"It's doing what every good school does," says Jones-Williams of the school's secret to sporting success.

"You want to make sure students dream big, make sure they're grounded. You've got to nurture them, encourage them, give them the opportunity, and the greatest gift as a teacher is not what they do in school but what they do after school.

"In Geraint's case, goodness me, hasn't he dreamed big."

Jones-Williams describes Thomas, a promising rugby union player in his youth, as not only a talented sportsman but gifted academically, too.

"He was a bright student," he says.

"He's not just someone who has got a great set of lungs and legs and can pedal faster than anyone else in the world, he's an amazing individual and that's the inspiration everybody gets walking down the wall of fame -- and it's adults not just students as well.

"The last three days the whole nation willed him on. I don't think any of us have got any fingernails left.

"But on that Saturday when we knew he'd won the Tour and could come riding down the Champs-Elysees toasting a glass of champagne, who would ever have believed a boy from Whitchurch in Cardiff could ever have done that?

"That's absolutely amazing. It's still reverberating around Cardiff, still reverberating around Wales."