For someone who has travelled afar many times on my own, that I should be anxious about going it alone is comical. The years have changed me. And I have become used to a certain companion by my side.

This article was produced by National Geographic Traveller (UK). Snaking almost 1,800 miles from its source in Germany’s Black Forest to the Black Sea in Romania, the Danube is best explored slowly.

This article was produced by National Geographic Traveller (UK). The Danube touches deep. Its landscapes are lyrical, its cities were built high and mighty by once-great empires, its history is as old ...