There will come a time in my life when I will unilaterally declare that I am too old, too cranky, too fat and too rich to take overnight buses. Fortunately (or unfortunately in the case of the rich bit) I am not quite there yet.

We are continuing our Greatest Hits tour of South America – we have stood on the edge of precipices at dawn while giant condors soar just feet over our heads, we have contemplated vicuna shawls in Arequipa, we have hiked twelve hundred vertical meters up and down the Colca Canyon to swim in a hot spring (brrrr!) and I have braved the hairdressers of Nazca (OK, and we have also flown low over the Nazca lines). Next stop is the Atacama desert and the high salt plains of Bolivia, but to get there we have to stretch hundreds of miles south across Chile to San Pedro de Atacama via the charming terminus of Calama, and this means taking the overnight bus. Now, we like to think of ourselves as being pretty hardy travelers, based on our tightly-budgeted gap year experiences, oh … 15 years ago, but in reality we are trying to ration the level of INTREPID on this trip:

• Not at all intrepid: being met at airports by hotel shuttles, hotels with chocolates on pillows (or pillow menus, or chandeliers in the showers – see Miami), guided tours, airport lounges
• Slightly more INTREPID: hiking without maps, tight-standing-room-only buses full of locals in traditional dress (and preferably full of chickens), navigating by the sun, hostel rooms with loos down the hall, altitude sickness and – to a certain extent – overnight buses

Which brings us to the night bus from Arica to Calama. Foreigners aren’t allowed to buy Chilean tickets from abroad, so we arrive in Arica (Northern Chile – keep up!) with our fingers and toes thoroughly crossed that there would actually be tickets to San Pedro de Atacama. Of course there aren’t, so we mill around the bus terminal avoiding the imaginary pickpockets, making friends with the local stray dogs (I must have trodden in a prime steak or something) and debating the best way South. Chilean bus services are actually pretty impressive, and so when we end up on a bus in the right direction we are pretty happy. We turn our two (reserved, but only reasonably proximate) seats into two adjacent seats by the time-honoured tactic of sitting next to each other, ostentatiously pretending to fall asleep hand in hand and being gringos. Result.

Lucy – INTREPID in Calama at 7am

The bus winds its way South across the desert for eleven hours along a variety of paved and unpaved roads. The lights go out soon after we leave and the locals fall asleep soon after, leaving the smattering of gringos peering out between the curtains at the unlit verges and trying to guess what scenery we are passing in the dark. A movie plays – not badly-dubbed martial arts like the day bus to Cabanaconde, but an uplifting tale involving butch firefighters and the power of Jesus in mending broken marriages (no, really). Lucy and I eventually fall asleep with our bottles of water on our laps, which hiss whenever opened as we gain altitude during the night. The air blowers go on and off, dispersing a subliminal underaroma of pee from the loo at the back of the bus. The rattle of the luggage racks and the hum of the engine are nothing compared with the night passages in the Galapagos, and we (well, I) soon fall fast asleep. A rude awakening at half past three: everyone onto the road to have our bags x-rayed for contraband, then back on board for a further four hours of snoozing before we arrive ahead of schedule in Calama. Chocolate chip cookies and plastic coffee in a chilly bus station for breakfast, and then we find our way onto the 8am connecting bus to San Pedro, looking forward to being horizontal, to stashing our slightly clammy money belts and to the probability of a warm shower.

Us wide awake on the connecting bus the morning after

You never know, we might actually get used to this.