Yesterday I wrote about my remarkable journey southbound across Switzerland via the breathtaking Bernina Express. 

For the homebound journey we opted for a faster itinerary: the Milan-Zurich express. Midway through the journey, drinking a coffee in the restaurant car, I noticed that we seemed to have been underground for quite a long time.

A while later, still underground, thinking this is a very long tunnel, I sought out a map. To my delight and surprise I realised we were zipping along the Gotthard Base Tunnel, which, at 52km, is the longest rail tunnel in the world.

What was so striking is how unremarkable this remarkable tunnel makes the journey. It is the opposite of the Bernina Express in so many ways, it is fast, straight, flat and has no views (at some point we will have crossed the watershed between the Po and the Rhine, but I was none the wiser).

In a sense, the immense effort to build this tunnel has made the journey effortless. A flattening that smooths the flow of goods and people between northern and southern Europe. The Milan to Zurich journey time shortened by an hour.

In their own times, both the Bernina and the Gottard routes were faster than what went before. Both a remarkable feats of engineering.