But these days we are all really at the centre of our maps, which is both a useful and egocentric thing. A thousand years ago Jerusalem stood at the centre of the Christian world view, or if you lived in China it was Youzhou. But now it is us, a throbbing green dot on our handhelds. We no longer travel from A to B but from Me to B, and we spread out maps on the floor or on our laps in a car only with wistful nostalgia.

It is quite possible to walk, phones in our palms, from one end of a city to another without looking up. The loss is historical, social and monumental (as one inspired tweeter observed, I wouldn’t change my Apple Maps for all the tea in Cuba). In our cars, GPS may guide us quite merrily from one country to another, and we may arrive at our destination without any idea of how we got there. En route from London to Cornwall, drivers may listen to a radio documentary about Stonehenge without realising that they have passed it on the right, for it is not on the sat nav. We now tend to look just a few yards ahead, which is a shorter distance than our ancestors used to gaze when they lived in caves.

Why modern maps put everyone at the centre of the world