"For me it was quite simple: The Oval is like the holy grail."
Wouter Schollema, from the Netherlands, knows a lot about groundhopping - so much, in fact, that he's literally written the book.
Groundhopping involves attending football matches at as many different grounds as possible.
Gracing the cover of Wouter's book is a famous slice of east Belfast history - the Oval, home of Glentoran Football Club.
"There is no better stadium for me. When I visited Glentoran I honestly fell in love with the club and the stadium," he says.
"The stands are old, it squeaks and cracks, there is just so much history over there."
Worldwide, the Bombonera stadium in Buenos Aires, home of Boca Juniors, is regarded as the number one destination for groundhoppers; the Oval, which overlooks east Belfast's famous Harland and Wolff shipyard, is seen by many as number two on the list and number one in Europe.
The resulting increase in the number of foreign visitors didn't go unnoticed at the Mersey Street club.
It prompted Simon Wallace, Glentoran's commercial manager, to create a dedicated groundhopper tour, now in its second season.
Sam Robinson, of Glentoran Community Trust, who leads the tours, says that the lack of development at the ground, long a source of embarrassment for many fans, is a major part of the appeal for groundhoppers.
"What we thought was a negative, turns out for European visitors to be a real positive if you want to experience a game of football the way football was experienced back in the 60s and 70s," he says.
"It's standing on terraces, it's the old architecture - the 1950s football stand, the view that the Oval gives you.
"When you walk into the boardroom at the Oval it's like you're walking back into 1967, you can even smell the history. It's a smoke-stained throwback to another era."
That's something that Wouter Schollema agrees with.
"The Oval is like a walk through time. When you're walking through east Belfast it's like the entire 20th Century passes your mind," he says.
"For some odd reason people tend to like stadiums that are straight from IKEA nowadays. But what's the point? There is no history in that.
"Whenever other groundhoppers ask me where they should go to, or if people even consider visiting a match in the UK, I always advise them to go to Glentoran."
Groundhoppers from the rest of the UK, the US, Canada, Holland, Italy and Germany have come to the Oval in the last year, with about 20 attending one of the Belfast derby games with Linfield alone.
Sam Robinson says while more visitors are coming, the club is determined that the tours remain both laid back and authentic.
"It's almost like a guerrilla tour - it's just actual fans showing them round their house," he says.
"We come in while the kit's being laid out for the matches, you know, it's an experience that they don't get.
"They're allowed to walk on the pitch, which for many of them's a real sort of experience to walk on a football pitch.
"The feedback we get from them is that pretty much everywhere they go is concrete and plastic and lacks soul, lacks heritage, lacks history, but there's so many elements to the Oval and so many stories to be told."
Among the stories visiting fans hear is the ground's destruction by German bombers during World War Two, the discovery of hidden loyalist weapons during the 1920s and how many of the team's players in the past also worked at the nearby shipyard.
Football stories include the winning of the Vienna Cup on the eve of World War One, how the club turned down boyhood fan George Best and how Italy and Juventus tough guy Claudio Gentile was humbled by Glens hardman Rab McCreery during a 1977 European Champion Clubs' Cup tie.
On a sunny September Saturday, visitors from Canada, the Netherlands and England take the groundhoppers tour, that also includes a match ticket and a pint.
As they walk on the pristine Oval pitch, the groundsman is busy painting the penalty spot with white paint, while some of the Glentoran players warm up on the pitch.
Among the visitors are a honeymooning couple from Vancouver, Canada - Paul Leeburn and his wife Terri.
"I was born in east Belfast - we emigrated to Canada in '75," Paul says.
"I set this up to show Terri the Oval, show her the Glens and relive my childhood, because I remember coming here, going through the turnstiles.
"It's just brilliant, it was a fantastic day."
Terri says she was "blown away".
"I just love all the history behind it. If you're going to come here [to Belfast], come here and find out about it, because you see such a different side of it."
Richard, from Holland, has been groundhopping for about 25 years.
"We're not here for the football game, we are here for the atmosphere," he says.
"It's great, lots of history. We've done many tours in Europe, but this is the one where you have freedom, you can go everywhere, you're one of the family."
Ken, from the West Midlands, says he has been trying to visit the Oval for three years, but previous games were moved for TV at the last minute.
"Parts of it [the ground] are old and decrepit, but that's what makes it," he says.
"These are real grounds with people who work here, they don't get paid, this is a way of life for them - they're worth a hundred plastic fans."
Wouter Schollema says the Oval's reputation continues to grow.
"The Oval has features you don't find a lot any more, you feel like you're really welcome and let's face it, if you want to experience real football this is what you're looking for."