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Martigny to Chamonix, France-Switzerland

This cross-border line linking Switzerland’s Valais region with Haute-Savoie in France is a tiddler among international rail routes and has never been used by grand expresses (even though it’s called the Mont-Blanc Express). The metre-gauge local railway from Martigny to Chamonix skirts the north side of the Mont Blanc massif and so connects standard-gauge lines on either side of the border. Climbing up from Martigny, there are tantalising glimpses of the ravine cut by the River Trient. The train passes great cliffs, twisting and turning with a feast of panoramic views. After crossing the French border at Vallorcine, look out for the Argentière glacier to the left.

• From €28.50 one-way, 22 miles, 90 minutes, hourly, mont-blanc-express.ch

Porto to Vigo, Portugal-Spain

Facebook Twitter Pinterest Campanha station, Porto. Photograph: Mark Dunn/Alamy

The facade of Campanhã station in Porto, with its Romanesque windows and imposing station clock, has a quiet authority. It is the starting point for the cross-border run to Vigo in Spain. The fortunes of this route have ebbed and flowed over the past 50 years. Rescued from closure, it offers a much-improved service these days. Leaving Porto, the train turns its back on the sea, heading north through hills towards the Minho region. Only an hour after leaving Porto is there a first glimpse of the Atlantic as the train crosses the Lima River to reach Viana do Castelo. There is drama about the final approach into Vigo, as the trains pass under the Ponte de Rande (which carries the Atlantic Highway over the Ria de Vigo) and runs along the waterfront into the city.

• €14.95 one-way, 109 miles, 2 hours 20 minutes, twice daily

Nice to Tende, France

Facebook Twitter Pinterest The narrow gauge railway between Nice and Tende. Photograph: Alamy

The main Riviera coastal rail route is always fun but the French département of Alpes-Maritimes has an intriguing branch line that offers a back-door route into Italy’s Piemonte region. So take that line from Nice to Tende, from where there are occasional onward trains to Cuneo in Italy. Skirting Nice’s smart suburbs, the train cuts through a long tunnel to reach the Bévéra valley and the town of Sospel. Then the route tracks north with fine views of the Gorges de Bergue to reach the mountainside town of Tende.

• €14.10 one-way, 44 miles, 2 hours 10 minutes, 3 daily, tendemerveilles.com

Ardennes Railway, Luxembourg

Facebook Twitter Pinterest The railway line from Luxembourg City passing through the Grund district. Photograph: Alamy

Start in Luxembourg City for this run north up the Alzette valley into the hilly Ardennes. This ride to Troisvierges has a feast of fine scenery. Leaving Luxembourg over a series of impressive viaducts, the railway climbs gently amid a medley of gorges, castles and forests. If you are minded to break your journey, Clervaux is a good place to stop. But why not just ride all the way to Troisvierges and back? It’s the perfect summer evening excursion and all the better from March 2020 when you can travel for free, as Luxembourg will have scrapped all public transport charges.

• €2 single until 1 March, 44 miles, 70 minutes, hourly

Limerick Junction to Waterford, Ireland

Facebook Twitter Pinterest Waterford’s historic waterfront. Photograph: Peter Cripps/Alamy

Travel by train around Ireland and you’ll eventually end up changing trains at Limerick Junction. However, only a handful of people change on to the train that rattles east along the branch line to Waterford. In a country blessed with many wonderful railways, this rural route is one of the finest, following the beautiful Suir valley for much of its length, and concluding with a dramatic entry into Waterford. Water meadows, castles and a medley of attractive towns make this the perfect diversion.

• €5.29 one-way, 56 miles, 1 hour 50 minutes, twice daily (not Sundays), transportforireland.ie

Madrid to Ávila, Spain

Facebook Twitter Pinterest El Escorial Monastery, seen from the Àvila train.

Photograph: Ian.CuiYi/Getty Images

Príncipe Pío station, a mainly commuter station north-west of central Madrid, is the unlikely starting point for a journey into the rural hinterland. An old mainline, now relegated in status, the railway to Ávila cuts through Madrid’s edgelands, a wilderness of industrial estates and, before long, is climbing towards the Sierra de Guadarrama. Suddenly, to the right, there is a gorgeous view of the monastery of El Escorial. That view is the prelude to an hour of pure theatre as the train winds up through wilderness. There are just two seasons up here, it’s said. Summer lasts a month, and then come 11 months of winter.

• €12.70 one-way, 76 miles, 90 minutes, 7-9 daily, renfe.com

Wernigerode to the Brocken, Germany

Facebook Twitter Pinterest The Brocken railway in Harz national park, Saxony-Anhalt. Photograph: Alamy

At 1,142 metres the Brocken breaks no records, even though it’s the highpoint of the Harz mountains. However, prior to German reunification in 1990, the Brocken was reserved for military use and out of bounds to civilians. It was 30 years ago this winter that 6,000 East Germans reclaimed the summit for the people. Not long thereafter the public rail service to the summit, which had been suspended in August 1961, was reinstated. Steam trains chug up from Wernigerode to the barren mountaintop, which is often formidably windy. The Eisenbahnschnapps (railway brandy) dispensed on board is gratefully appreciated.

• €29 one-way, 21 miles, 1 hour 50 minutes, 3-6 daily, hsb-wr.de

Teplá Railway, Czech Republic

Facebook Twitter Pinterest A railway bridge over Tepla River. Photograph: Michael Nosek/Getty Images

The reputation of the Czech spa town of Karlovy Vary relies on the healing waters from springs in the Teplá valley. In-the-know visitors take the train to Mariánské Lázně, for a ride as therapeutic as the spa waters. There is nothing quite like a slow rail journey to revive tired bodies and troubled minds. The railway from Karlsbad to Marienbad – as the twin spa towns were known when the line between them was completed in 1898 – was a fine piece of Habsburg ingenuity. It is a lovely “up-and-over” route through hilly terrain which, for the early part of the ride, climbs slowly up the valley. Sit back, relax, and let the forests slip by.

• £2.40 one-way, over-60s 60p, 33 miles, 75 minutes, 8 daily, cd.cz

Oulu to Kuopio, Finland

Facebook Twitter Pinterest Kajaani’s art nouveau station. Photograph: Esa Hiltula/Alamy

A wonderful secondary route from Oulu, on the Gulf of Bothnia in central Finland, runs south-east inland through Kajaani to Kuopio, playing cat and mouse with the Oulu River as its heads into a land of lakes and forests. The mid-point is Kajaani, whose art nouveau wooden station is painted in muted shades of grey and cream, reflecting the landscape. South from Kajaani, the train rolls past farmsteads and cottages with picket fences. Wooden churches add to the magic of the journey.

• €39 on the day, advance saver tickets from €19.70, 225 miles, 4 hours, 3-4 daily, vr.fi

Septemvri to Dobrinishte, Bulgaria

Facebook Twitter Pinterest Villages in the Rhodope mountains. Photograph: Alamy

The small railway town of Septemvri, coaxed into life as the rail route from Istanbul to Vienna arrived in 1873, is the unpromising start for the narrow-gauge train into the Bulgarian hills. The branch line to Dobrinishte isn’t built for speed: fierce gradients and tight spirals mean progress is often painfully slow – but that brings its own blessings. There are superb views of three mountain ranges: the Rhodopes, the Rila and the Pirin. Along the way, this slowest of slow trains crests a ridge before dropping down into the Mesta valley. Look out for snake eagles and white storks, rock partridges and calandra larks.

• £2.80 one-way, 78 miles, 4 hours, 4 daily, bdz.bg

• Nicky Gardner is co-author of Europe by Rail: The Definitive Guide. The 16th edition of the book is out now. To order a copy for £14.95 visit the Guardian bookshop

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