The actors, who will reprise their roles respectively as Wolverine and Professor Charles Xavier in upcoming follow-up X-Men: Days Of Future Past, unveiled an 11-car Pendolino train which features the characters of the comic book franchise on the carriages at London's Euston station.
Jackman, 45, admitted getting a train with his face emblazoned on it was a far cry from his earlier days when he backpacked around Europe.
He said: "It's some sort of wish fulfilment in life, when you're a young boy, to walk onto your own train.
"I pretty much lived on trains (before), because when I was 18 I got an InterRail card. It was about £250 and I was on £10 a day, so we slept on trains.
"I was that smelly guy in the corner, just outside the bathroom that people would have to step over.
"I would be swearing and drinking with my mates, so I got kicked off from many a train."
The Australian actor joked about McAvoy appearing on the first-class carriage, with Jackman's carriage located further back, saying: "I think it's totally appropriate that he's first-class and I'm way up the back. It's pretty wild!"
McAvoy - who was awarded the best actor prize at the 2014 Jameson Empire Awards - said seeing his own train carriage was quite a surreal experience.
"I feel like I came in during the night and graffitied it, and this is the result. When I told my son, he told me it was 'train-tastic'!" he said.
Phil Whittingham, from Virgin Trains, added: "For us, it's all about our relationship with speed. The latest instalment in the X-Men franchise ties in perfectly with Virgin Trains' relationship with travel.
"Time travel is a key theme throughout the new movie and at Virgin Trains, we strive to make sure our customers' journeys are as quick as possible, as if our trains are time-travel devices."
Both Jackman and McAvoy will be joined by the new generation of X-Men stars like Michael Fassbender, Jennifer Lawrence and Nicholas Hoult, as well as older cast members such as Sir Ian McKellen, Sir Patrick Stewart, Halle Berry and Ellen Page in Days Of Future Past, which is directed by Bryan Singer.
"It is epic-ness, it is huge on a scale, not just visually but emotionally. Character and relationship-wise, it is quite epic with what we all go through," McAvoy teased.
Jackman added: "It is massive. It is by far the biggest.
"I had this unbelievable opportunity to work with not only James and Michael Fassbender, Jennifer Lawrence, but the older actors playing the same characters - Ian McKellen, Patrick Stewart, Halle Berry, Ellen Page.
"It was unbelievable and the story is intricate. It is fun, it is massive and I think it is going to deliver beyond what people expect."
X-Men: Days Of Future Past will open in cinemas on May 22.