A long-awaited rail link between Finland and Sweden is finally set to launch this June, opening up what could become one of Europe's longest rail journeys. Finland confirmed a £1.65million financing deal for the cross-border route last week, linking Tornio in Finland with Haparanda in Sweden, and both countries have signed an agreement to simplify rail traffic, according to euronews.

Passenger trains previously connected the border towns, but services were suspended by both countries in the late 1980s to early 1990s. Since then, travellers have had to rely on buses or cars, despite railway lines existing on both sides. The gap stems from a long-standing technical difference. Finland uses a wider track gauge of 1524mm, dating back to its time under the Russian Empire, while Sweden uses the standard European gauge of 1435mm, preventing direct services.

To work around this, a historic station in Haparanda, Sweden, originally built in the early 1900s, will be restored to act as a transfer hub. Passengers will step off one train, walk through the station, and board another on the neighbouring track.

"Finnish VR trains will stop at the Tornio C station and then terminate at Haparanda," Sampo Kangastalo, development director of Tornio, told Yle News.

"The Haparanda station building is located between the Finnish and Swedish tracks. So to change from VR to Swedish Norrtåg trains, you'll just walk through the station building - it's easy."

He said the grand opening will "hopefully" happen in late June. Once open, the route could unlock what is believed to be the longest rail journey possible within the EU.

According to railway consultant Jon Worth, it may be possible to travel from Finland's northernmost station, Kolari, all the way to Lagos in southern Portugal entirely by train.

"As far as I can tell, Kolari to Lagos, Portugal, is the longest journey you can take on multiple trains within the EU," he said.

The link is also expected to improve travel across northern Europe, giving cities like Rovaniemi and Oulu in Finland rail access to Sweden without the need for flights or ferries.

It could even provide an alternative to the roughly 18-hour Helsinki-Stockholm ferry, with a train journey taking just over 24 hours.