While leaf-peeping in the Upper Engadine valley, Kate Simon welcomes the changing of the seasons

The view through my train window is too green. The forests of pine that clad the surrounding slopes of the Swiss Alps remain as regimented in shade as form. Yet, I am on my way to the Grand Hotel Kronenhof in Pontresina to try out a special package designed to encourage guests to view the glorious autumn colours of the Upper Engadine Valley.

The scene is certainly glorious, irrespective of the lack of autumnal colour. I am riding the Glacier Express, a little red train that scuttles up the Alps from Zermatt to St Moritz, crossing vertiginous viaducts, and popping in and out of holes in the mountains as it goes. The stretches of track in the Albula and Bernina landscapes are architectural and engineering feats, now recognised by Unesco in its list of World Heritage Sites.

Ever higher we climb, but still the screens of pine trees offer no contrast for the eye. I pull out the hotel's publicity material, which assures me the Swiss Alps can easily rival the great autumn shows of North America. It says that nothing announces the arrival of the new season quite so dramatically as the "striking red, glimmering gold and burnt orange" leaves of the trees of the Engadine valley. I look back through the window; if I screw up my eyes, I can just about make out a frond of yellow, deep in the canopy.

By the time I reach the hotel and meet Flavio, my guide for a leaf-peeping tour of the area, I'm almost in despair. It seems my arrival in late September is just a little too early in the season to bear witness to this natural phenomenon.

"If you wait another couple of weeks, then you will see the trees changing colour. It's starting – you see a yellow tree here and there – but soon the whole forest will be a mixture of greens, browns and oranges."

Flavio is not just a guide; in summer he also works as a forester. "We're in an avalanche zone, so it's really important to cut the trees to ensure they're healthy," he tells me. "They provide a natural barrier. They fix the snow."

It seems to me, a forester who is also a guide is a great asset on a leaf-peeping trip. However, it turns out Flavio doesn't need to have swallowed a book on tree identification; he says there are only three kinds that grow this high up in the mountains – the red pine, the arve (aka the Swiss pine) and the larch. It's the larch that causes the colourful commotion in the otherwise evergreen canopy, turning to shades of yellow and orange.

Flavio tells me that, when the autumn leaves are in full show, I'd be able to step out of my hotel and take any path or railway track into the mountains to enjoy the sight. For now, we must actively seek out any turning leaves, so he takes me to the shores of two of the main lakes of the Engadine valley – Silvaplana and Staz – to uncover some early signs of autumn. There, by the cold, clear waters, we find a few larches shaking out a yellow branch or two.

But, my attention is captured by the mountain tops. This is the roof of Europe, somewhere I've seen before only from the window of a plane. Our distance from the seashore is evidenced by the treeline, the point at which nature cannot summon up the strength to germinate another seed. Where there are no trees, there is the brown mulch of dead alpine rose, edelweiss and primrose and, at the very peaks, just cold, hard rock, nude yet of snow. This looks more like autumn to me.

Travellers have come to the Upper Engadine for centuries, attracted by the views, which can often be admired in bright sunlight (this area gets more sunshine hours than anywhere else in Switzerland), and sparse cloud cover. Yet, on the second day of my visit, a storm settles into the valley, and I am confined to the hotel.

This is not a new challenge for the Kronenhof, which originally opened in 1851 as a guesthouse for Switzerland's army of postmen. The explosion in tourism to the Upper Engadine in the 1870s spurred on numerous improvements that brought it rather more upmarket.

These included a "Bellavista" wing of gracious salons, set against the backdrop of the mountain panorama, the best place from which to view the ghostly spectre of the Roseg Glacier, which never removes its white winter coat. Amid these drawing rooms, the visitors who enjoyed extended stays here, made necessary in the 1800s by the remoteness of this Alpine retreat, could while away days of poor weather playing bridge and billiards, and even bowling in the specially constructed alley.

Today's guests can still play all those traditional games in the carefully preserved rooms, but they are more likely to head to the new spa, a contemporary space as bold as the 19th-century confection on which it has been bolted. I take a swim in the vast infinity pool that sits beneath its central dome, pausing at the water's edge to look through the wall of windows at the mountains beyond. But my eye is caught by something in the foreground: it's a larch that has turned almost fully yellow. Autumn is definitely on its way.


Getting there

Kate Simon travelled to Zurich with British Airways (0844 493 0787; ba.com/zurich), which flies from Heathrow and London City to Zurich from £135 return. Alternatives include Swiss (0845 601 0956; swiss.com) and easyJet (0843 104 5000; easyJet.com). The writer took the train from Zurich to Pontresina. A Swiss Transfer Ticket for a round trip between the airport or border and destinations across the country costs from £90 (00 800 100 200 300; swisstravelsystem.co.uk).

Staying there

The Grand Hotel Kronenhof (00 41 81 830 30 30; kronenhof.com) offers a two-night autumn package until 20 October. It costs Sfr415 (£273) per person, based on two sharing, with breakfast and dinner included, unlimited use of the mountain railways in the Engadine/St Moritz area and access to the spa.

More information

myswitzerland.com. glacierexpress.ch (which runs until 28 Oct and starts again from 9 Dec)