The railways a tour is built around

A good scenic railway solves a problem that roads generally cannot: it gets a large window right up against genuinely difficult terrain without making anyone drive through it. Mountain ranges tend to have a handful of these lines, built originally for freight, mail or simple necessity, and repurposed over the following century into some of the best travelling a tour itinerary can offer. Three, in three very different mountain systems, turn up again and again in escorted tours for the same reason: nothing else covers the same ground half as well.

What unites them is not comfort, exactly, though all three are comfortable enough. It is the angle. A coach window shows the road; a train window, freed from the business of steering, shows the valley whole, with none of the driver's attention required for the view to hold. That difference is worth more to an itinerary than an extra stop would be, which is why operators build entire days around a few hours on rails rather than treating the railway as one excursion among several.

Switzerland's glass-roofed classics

Switzerland has more scenic railway than any country its size has any right to, a consequence of nineteenth-century engineering ambition meeting genuinely spectacular terrain. The routes that tours build days around, connecting Interlaken, Lucerne and the high passes towards Brig and Chur, run with the country's famous punctuality through valleys and over viaducts that a road would have to tunnel beneath rather than cross above. Vitznau, on Lake Lucerne, is also the base of Europe's first mountain rack railway, opened in 1871 to reach the summit of Rigi, a piece of engineering history that predates the more famous glass-roofed trains by decades.

Canada's Rocky Mountaineer

The Rocky Mountaineer runs, daylight only, between Calgary and Vancouver by way of Banff, Lake Louise, Kamloops and the Fraser Canyon, and the daylight-only rule is not an accident: the railway deliberately stops overnight in a hotel rather than running through the dark, on the sound theory that nobody pays this kind of money to sleep through the Rockies. The line itself follows routes surveyed and built in the nineteenth century for the transcontinental railway that first stitched Canada together, through terrain so difficult that construction crews spent years blasting and tunnelling through the Fraser Canyon alone.

Sri Lanka's hill country line

The railway through Sri Lanka's central highlands, connecting the tea country around Nuwara Eliya with the town of Ella, is a smaller, slower affair than the other two, and arguably more atmospheric for it. It climbs through tea plantations and cloud forest on a line built by the British in the nineteenth century to move tea to the coast, crossing the Nine Arches Bridge near Demodara, a viaduct built, according to local tradition, without any steel at all after supplies were held up during the First World War. Doors are generally left open, which is either the making of the journey or faintly alarming, depending on temperament, and the slow pace through the tea estates gives a much closer look at how the leaf is actually grown and picked than any coach stop at a factory could manage.

Why tours build around them

None of these lines exists because a tour operator invented it for the view. Each began as serious infrastructure, built to move tea, freight or passengers across terrain that resisted roads, and each has simply outlived its original commercial purpose to become the best possible way of seeing the ground it crosses. A tour that reroutes a whole day to fit one of these journeys in is not padding the itinerary; it is admitting that the railway does the job better than the coach ever could.

It is worth saying, too, what these journeys do not offer. None of the three is fast by the standards of modern rail travel, and a passenger expecting a high-speed train with a view has misunderstood the appeal. The slowness is the point: a line built through terrain this difficult was never going to be quick, and the pace is exactly what allows a passenger to actually look at the country it crosses, rather than simply pass through it.