The country's only remaining narrow-gauge railway line plays host to heritage trains, offering travellers a chance to travel through the stunning Vouga Valley in a period locomotive.

We're gathering speed as we rumble east from Portugal's coastal city of Aveiro. Modern apartment blocks outside the train's open windows yield to ivy-covered trees, then pastel-hued farmhouses dotted among lush green fields. The refreshing scent of eucalyptus replaces the faint diesel fug in the carriage – resplendent with hardwood benches and drop sash windows – and the conductor sounds the air horn at the townspeople waving from their terraces, gardens and balconies, thrilled to spot us.

Plan your trip:

The Vouga Historical Train runs Saturdays in July and August, departing from Aveiro at 13:45 and returning from Vouga at 20:07. Tickets cost €41 (£35) and €25 (£21) for children. Dates for the festive steam train service, which runs from late November to early January, are announced each autumn.

Why such an enthusiastic welcome? Because this isn't just any train. This is the Vouga Historical Train, a vintage locomotive that runs through the verdant Vouga Valley on Portugal's only remaining narrow-gauge railway. Comprised of a navy-blue 1964 Basque Railway diesel locomotive and five early 20th-Century carriages, "the Vouginha" – as it is affectionately known by locals – is a beloved summer visitor, trundling along a twisting 46km stretch from Aveiro to Macinhata do Vouga and back as part of a six-hour excursion that also includes a visit to the artsy city of Águeda. Each summer, locals and travellers alike can climb aboard for a unique railway journey into the past.

Constructed between 1907 and 1914, the Vouga line originally consisted of three branches, extending 96km north to the city of Espinho and 140km east to Viseu, with the town of Sernada do Vouga acting as a central hub.

"This series [CP 9000] of locomotives were working in the mines of Spain, then Portugal bought three or four of them," says driver Pedro Cabelo, who has worked for national rail firm Comboios de Portugal since 2008. "The Vouga line was originally for people to travel between the cities in the interior land."

At 668mm narrower than standard Iberian-gauge railways, the metre-wide tracks that twist and turn through the valley's famous forests and bridges were cheaper and better suited to the winding routes when they were first laid, but eventually became economically unviable due to maintenance costs and limited capacity. Passenger services declined and ceased entirely by 1990.

But starting in 2009, sections of the track were converted into ecotrails for cycling, running and hiking, culminating with the 2023 unveiling of the Ecopista do Val do Vouga, a path/trail that completed the 80km route between the towns of Sernada and Viseu,........

© BBC