The longest public transport journey in Switzerland is not what you might think. For one thing, it both begins and ends in the same place. And for another it is not on one of Switzerland’s famously efficient, much-photographed and fetishised trains.

Every day from the end of June to mid-October, a Postbus sets off from the resort town of Meiringen in the Bernese Oberland for a nine-hour lasso of the Alps. En route, it clambers over four of Switzerland’s lofty mountain passes, only clear of snow in summer, including the Gotthard, the so-called “king of the passes”, since the Middle Ages a vital trade route across the Alps, between northern and southern Europe. This summer marks the centenary of the first Postbus crossing of the Gotthard — though there is minimal fanfare for the humble bus — and I was lucky enough to be on the first run of the year.

We were an odd bunch boarding that morning. Some bus enthusiasts, some serious mountaineers with ice-axes, taking advantage of a fair forecast. Some mountain bikers with ropes, for God knows what. A couple of engineers en route to hydroelectric installations. And some, like me, who were in it simply for the chance to inspect the roof of Europe from a comfy seat.