Take the train from Switzerland to Europe

The Swiss resort of Interlaken, which as its name suggests, sits between two lakes, has a surprisingly oriental hue. The greeny-blue mountain-cupped lakes - Thun and Brienz - on either side are a slice of postcard Switzerland, so primped and pretty that they're almost a cliché. The town itself is unexpectedly busy with people from Japan, China and the Middle East: most are here for the scenery and the chance to get up into a spectacular snowy wonderland at almost all times of year. There's a star-struck element at work here, too, because a lot of Bollywood blockbusters have been filmed in the surrounding mountains, and their legacy is a huge fan club of visitors from the Indian subcontinent. The key that unlocks that wonderland is a different kind of star attraction: a venerable, spectacularly engineered railway, which is celebrating its 100th anniversary. The route that it travels to the top of Europe leads right up to a ridiculously high station lodged on a ridge - the Jungfraujoch, which at 3,454m is the highest railway station in Europe and among some of the highest peaks in the Alps. For a big proportion of the visitors in Interlaken it presents the opportunity for those who have little experience of snow to get up in the cold white stuff without having to go through all the farrago of strapping skis to their feet. The railway journey up to the Jungfraujoch can, depending on the time of year, start with T-shirts and balmy sunshine, and end, a couple of hours and over 3,000 metres of climbing later, in sub-zero conditions, with fellow passengers almost unrecognisable under hastily-donned layers of clothes. But you do have to choose your day and your weather conditions to be sure of not wasting your money on a whiteout, and there are bad days when Interlaken remains chock-full of the tourism equivalent of migratory salmon, waiting for conditions to change before they surge upstream. I was lucky, starting out on a blue-skied autumn day when the foliage was still on the trees. The light was so sparklingly clean it almost squeaked. My journey began in Interlaken with Bob, also known as the Berner Oberland Bahn, a blue-and-cream liveried train which scurried happily up into the steep-walled alpine valley towards Lauterbrunnen, alongside a river the colour of glacier mints, which seemed to be telling tales of its mountainous descent as it tumbled towards the comfort of welcoming lakes. As Bob climbed into a land of sloping meadows peppered with typical alpine timber-built farmhouses like big-hatted cuckoo clocks, the train slowed momentarily to engage a cog in between the tracks to help it up the slope. There was a lot more of this cog-wheel traction to come, because at Lauterbrunnen passengers have to pile out of Bob and into the diminutive old yellow-and-green liveried coaches of the Wengernalpbahn, on the platform next door. Instantly, it felt as if we'd travelled back at least 50 years, and this Lilliputian train rattled arthritically out of the valley bottom as if it was auditioning for a part in a model railway, posing questions in my mind whether it was really up to the job - questions it quickly answered by taking to the mountains like a gazelle. Now we were into serious climbing territory, as the coaches started to do their slow waltz up through tunnels and cuttings chiselled out of the rock face, ambushing waterfalls and looking down on wheeling birds of prey. After a long stop in the superbly-sited, car-free old resort of Wengen, basking in alpine meadows in the autumn sun, we moved on upwards, swapping the land of flower beds and vegetable patches for deciduous forests, which were to be followed eventually by conifers and then bare rock and the threat of snow. By now we were seriously high. At the junction of Kleine Scheidegg passengers need to change trains again to the Jungfraubahn, and it's a good moment to stand and gawp at the huge north face of the Eiger mountain, and the next-door Jungfrau, looming above. In summer, the Eiger's face is one of the ultimate challenges for climbers, 69 of whom have died here since 1935 while attempting to conquer it. I decided to take time out to have a coffee on the terrace of the Eigernordwand restaurant and scan the massive wall of rock, feeling a bit anxious in case I should suddenly witness a distant drama, but I couldn't spot anyone making the climb that autumn day.