Leave the M4 motorway at Junction 24 in south Wales, head south along the tree-lined A48, cross the railway bridge, swing past the retail park, circle behind the athletics stadium and you arrive at Dragon Park.
The complex in Newport, 16 miles northeast of Cardiff, is the home of Wales' National Football Development Centre, and in recent years its corridors and training pitches have been trodden by a galaxy of world-famous football personalities studying for their coaching badges under the auspices of the Football Association of Wales.
Thierry Henry and Patrick Vieira are two of the centre's most well-known alumni, and on Wednesday, 740 miles away in southeast France, the lessons they learned at Dragon Park will be put to the test when Henry's Monaco and Vieira's Nice face off in Ligue 1.
Their paths diverged sharply over the years that followed—Vieira becoming a world and European champion with France and winning a host of major honours at club level, while injury forced Harrison out of the game in 2003—but when they met for the second time, it was as equals on the UEFA Pro Licence course at Dragon Park in March 2014.
"You used to see him on the pitch—and I was fortunate to play against him when I played for Middlesbrough—and he was such a ferocious competitor. He's such a different person off the pitch," Harrison tells Bleacher Report.
"He's soft-spoken, he's kind, he's very well-mannered, he's approachable, and he'd quite happily have a conversation with someone like me or another Welsh Premier League manager."
The 16 other people on the pro licence course with Vieira and Harrison included such former Premier League stars as Craig Bellamy, Les Ferdinand, Tim Sherwood and Sol Campbell, as well as the then-Swansea manager Garry Monk. Harrison was the manager of Welsh top-tier side The New Saints, but although he could not hold a torch to his class-mates when it came to elite-level experience, he never felt out of place.
"Whether it was me, managing TNS, or Garry Monk managing Swansea in the Premier League, everyone rolled their sleeves up and dug in together," says Harrison, who went on to set a world record for consecutive top-flight wins with TNS in 2016.
"Because it was out of everyone's comfort zone, everyone felt on the same level. You were doing things that you hadn't done before. When people were just about to present in front of the group, everyone was nervous. Patrick wasn't any different to anybody else."
That sense of democracy was one of the things that attracted Vieira to the FAW's coaching programme in the first place. As he explained to The Guardian in August 2013, shortly after starting the A licence course: "I chose a place where I feel comfortable to learn, where there are no egos and where they treat everyone the same."
Officially opened by Michel Platini, another former France great, in April 2013, Dragon Park is a purpose-built facility where coaches can make use of cutting-edge technologies such as Globall Coach tactical animation software and drone-mounted cameras to film training sessions.
The centre's coaching courses, overseen by FAW technical director Osian Roberts, have earned a global reputation for producing progressive, tactically astute coaches. The list of graduates also features Marcel Desailly, David Ginola, Mikel Arteta, Freddie Ljungberg and Jens Lehmann, with word of mouth helping to keep a steady stream of football luminaries passing through the entrance doors.
"I met Osh [Roberts], and the way they see the game and the way they were doing things in the FAW, the identity and the philosophy about the game is how I see the game," Henry told reporters who visited Dragon Park in May 2015. "It was the perfect match."
Henry, 41, began studying for his coaching badges in Newport in early 2015, achieving his A licence in March 2016 and completing his pro licence course in January 2018. As with Vieira, his classmates were impressed by his humility and eagerness to learn.
"Thierry was fantastic," says Colin Caton, manager of semi-professional Welsh club Bala Town.
"There were four or five non-league lads on the course, but he wanted to know about our experiences as well, how we did it on a part-time basis. He was astonished that lads would be going to work and then having to train and play at night."
Caton was touched that, after completing the pro licence course, Henry made a point of hailing Bala Town's victory in the 2017 Welsh Cup in an interview published on the FAW website. The members of that 2017-18 pro licence cohort remain in touch via a WhatsApp group.
The group would assemble at Dragon Park for three to four days, every other month, over a period of 18 months. They stayed at Celtic Manor, the luxury resort just up the road that staged the 2010 Ryder Cup. Their days were spent following the various course modules (player fitness, match analysis, dealing with the media etc.), preparing training sessions and listening to talks delivered by guest speakers.
When the working day came to an end (sometimes after 12 hours of contact time), the exchange of ideas continued. Over dinner or while sitting around watching live games on television, the coaches would chat about tactics and playing systems, occasionally picking Henry's brains for insights into playing under Pep Guardiola and Arsene Wenger.
"We'd sit around the classroom table once we'd finished and have a good chat about different things," says Caton. "It was the same at dinner and the same at breakfast. When we'd finished, we'd go and have tea together and speak about formations and everything. We didn't just learn once the class started. You learned every time you were with someone travelling in the car from Celtic Manor to Dragon Park. It was football non-stop."
So did the time that Henry and Vieira spent at Dragon Park provide any clues as to the kind of coaches they would go on to become?
"[Vieira] knew what direction he was going to go," says Harrison. "Sometimes you need to mix things up a bit, but his style was always going to be passing teams that play through the thirds and try to control the game with possession. Very much like the Arsenal team he played for and the Man City team he was working with at the time."
Henry has regularly lauded the style of football he played under Guardiola at Barcelona, describing the Manchester City manager as his "reference point," yet Roberts believes he is savvy enough to know that he will have to tailor his approach to the players at his disposal.
"To define him as a coach, I'd say that he's pragmatic and realistic," Roberts told L'Equipe in October.
"The fact that he was a forward doesn't mean he'll adopt an attacking style of play at any cost. I can't imagine him being delighted by a 5-4 victory. Similarly, the fact he played under Guardiola at Barcelona doesn't mean he'll adopt a possession game.
"Thierry knows that he'll have to adapt to his squad and that it'll take time before he can introduce a real playing philosophy."
Vieira, 42, made an impressive start to life as a head coach with New York City FC, leading the team to successive play-off appearances in 2016 and 2017 despite simultaneously bringing down the squad's average age.
After a slow start at Nice, where he failed to win any of his first three Ligue 1 games, he has led the team into the top half of the table. Despite Les Aiglons ("The Eaglets") having the joint-worst attack in the division, they are only four points off the Champions League places going into Wednesday's match against local rivals Monaco.
Henry's attempts to impose a style of play at Monaco have been complicated by a scarcely believable avalanche of injuries. But although his side remain in the Ligue 1 relegation zone, an unbeaten start to 2019 and the arrival of January recruits such as Cesc Fabregas suggest there may be better days ahead.
Vieira and Henry have lifted trophies together with Arsenal and France, played in Italy and experienced life in New York, but when they are standing along from each other on the Stade Louis II touchline on Wednesday, intently analysing their respective teams' performances, the principles shaping their thoughts will be the ones they learned in a classroom in a quiet corner of southeast Wales.