There's a buzz in the air around Pontresina train station, where hikers, bikers, and day tourists are gathered in the morning sun. It's dazzling now after an ethereal start, the valley cloaked in a thin veil of mist. Cherry red trains chug in and out of the station, and to each one Albie cries "choo choo" and points in rapturous excitement.  

We're not boarding a train, but instead the Pferde-Omnibus. It's a sunshine yellow affair with three sturdy steeds roped on who will pull us halfway up Val Roseg, one of the prettiest side valleys in the Upper Engadine. It's exquisite: the glacier shines like marble at the top of the valley, where it is embedded in the pristine, powerful Bernina Massif. 

Not far into the valley we almost collide with a biker who waves his fists and shouts effuse angry words in a Basil Fawlty comedy moment that probably doesn't have the desired effect. We soon lose sight of the view as it becomes obscured by a leafy web of tangled larch, stone pine and rowan trees. Stray branches brush our faces as we hurtle along the track. As we follow the icy, gushing river up the valley we pass a meadow of cows wearing huge bells, and a multitude of bikers and other carriages, all clamouring for space.

From the shade, the landscape suddenly opens up onto the broad valley bottom, grassland spreading until it meets rock and then ice. The sun dazzles in this natural amphitheatre, where our journey ends at Hotel Roseg Gletscher. We pat Wanda, Maggie and Flurina in thanks; their flanks are lathered from the effort of climbing into the valley. We, in turn, have taken the easy option: it's all downhill from here. 

The path leaves the plateau and ducks back into the woodland, meandering above the river on the opposite, and sheerer, side of the valley to which we arrived on. There are gigantic boulders and dainty fairy pools draped in juicy red rowan berries, so heavy the trees' branches are bowing under the weight. All this red in the landscape - the berries and the Rhaetian Railway trains that streak through Pontresina - is as if put there by an artist. But it's nature's perfect eye, captured here in the Upper Engadine like nowhere else on earth. 

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