Then we entered the vast, empty land and the complexity of modern work and progress disappeared in the rear view mirror. Here, in the 18th biggest country in the world and the third least densely populated, economic activity means horses, sheep, goats and camels – and the occasional human being to look after them. That’s the way it’s been for generation after generation, and despite an economic revolution elsewhere in Mongolia, that’s the way it’s stayed.

Our first stop was at an ovoo: not a sentence I’ve been required to write in the course of my travels before. But then you’re likely to notch up a whole list of firsts on your first trip to Mongolia.

An ovoo is an improvised shrine. This one was about the size of small car. Anu, our guide, asked us to pick up a pebble. We tossed the pebbles on the mound of jagged sandstone rocks. Then we walked around it three times, in the proper Buddhist manner. I stopped in an equally Buddhist manner to avoid squashing a desert gerbil as it scurried between fist-sized holes made obliquely into the sand.

You see ovoos – some as huge as temples, others no more than cairns a few feet high, some of them many centuries old – throughout the country. The Communist authorities tried to abolish ovoo-building and worship. Good luck policing that in a country where there are 1.9 people per square kilometre – and most of them live in the capital.

Each ovoo supports a weathered pole and the wires of the prayer flags: blue for sky and space, white for air and wind, red for fire, green for water, yellow for earth.

Back in the car, I thought how the landscape stretching out before us seemed elemental, too, pared back to a handful of colours, textures and shapes. As the morning wore on, only a gauzy mist covered the naked planet. The soft green hills and dark rocky outcrops were like tiny islands in a limitless ocean of grass, scrub and sand.