The cat, named Junior, was found after its picture was posted on Facebook by a fellow passenger, owner Michael Rozek Høi told local newspaper Fredericia Dagblad.
Junior, said to be independent by nature, was missing for several hours on Sunday before returning home that night after an unusual excursion for a feline – including the 13-minute rail journey.
It is not known whether Junior took rail operator DSB's fast intercity train or the more leisurely regional service north.
“This cute, affectionate kitten hopped on board the train Sunday morning in Fredericia and hopped off in Vejle… I hope it gets home again safely,” Kristina Heinsvig Stabell wrote in the public Facebook group Kattesiden Fredericia og Omegn (Cat page for Fredericia and local area) after managing to take a photo of Junior on the train.
Michael Rozek Høi brugte flere timer på at lede efter sin kun 12 uger gamle Junior, men katten var taget på... https://t.co/ddSTDCLUS1— Fredericia Dagblad (@frdbdk) July 24, 2017
The 12-year-old pet was not receptive to being picked up and left the train alone, according to Stabell.
“It's nice to hear he's home again,” she later told TV2.
Høi told Fredericia Dagblad that the kitten had sneaked out of the house Sunday morning.
“It was raining, so he went to get shelter in the garage. Suddenly he then went to the station, so it seems,” Høi said.
Høi also took to Facebook, posting a message in the hope of tracking down Junior, who was then spotted relaxing on a woman's terrace in Vejle.
Høi set off to the town armed with a tin of cat food and was eventually able to retrieve his four-legged friend.
“I had a tin with me which I tapped on, and suddenly I heard something meow,” he told Fredericia Dagblad.
The now-peckish Junior was then treated to a second journey – this time back to Fredericia by car.
The kitten's owner said he is now planning to have the animal tagged.
“I told Junior not to do it again,” he told TV2.