Dear All

I write from the Inca Trail, where darkness has just come down like an axe over the 3,500m-high patch of grass we're sleeping on for the night.

The guides have been trying to make a campfire, but the wood has been dampened either by rain or the freestyle urinating habits of passers-by. The tour group - destination Machupicchu - has assembled to fight over tents, which have been packed together to form a kind of canvas housing estate with sheer drops on three sides. Either our charms or our early arrival have secured Josh and I a good one that looks like an igloo, and the German couple, struggling at the rear, have been palmed off with the mouldy triangle that nobody wanted.

The reason the Germans lagged behind was because they are both carrying very large rucksacks. We all have the same guidebook, and in it we are advised not to exploit local boys by paying them to carry our bags. At the head of the trail local boys are fighting to carry our bags, then collapsing pantomime-style under them. We selected Jorge to carry ours on account of his looks. Jorge, it turns out, is carrying at least four huge bags and is coining it. One unemployed porter bearing a resemblance to Ratso Rizzo in Midnight Cowboy actually followed the Germans all the way up the mountain, waiting for them to crack.

Everyone idles while the guides cook, except the Germans, who remove slippers from their rucksacks and change into them. Then they bring out a set of glass and steel condiments. Josh doesn't say much, but then he hasn't since that boy sat on his lap for 15 hours on a bus in the Bolivian jungle and emptied the contents of his stomach, bladder and bowels all over him.

Sue, who is here with Harry, approaches me and says she's heard I've written a book.

'What kind of book is it?' she says. I tell her it's a novel.

'Is it a fictional novel?' she inquires. I tell her it is.

Harry and Sue have an argumentative style of travelling, where Harry forges up the trail as fast as he can and then sits on a rock watching Sue toiling up below through a pair of binoculars. Both of them talk desperately to other people and give away important details, such as the fact that Sue's father is incredibly rich (Harry), and that Sue is not very intelligent (Sue).

It's very cold up here so we've put on all our clothes, including swimming costumes. Josh goes to take a photograph of the moon, which is full and has risen from behind the mountain like a white sun. Tomorrow is the hardest part of the ascent. Ratso has reappeared and is now trying to persuade the Germans to hire a horse. They remove a large bag of muesli from their rucksack and contemplate it.

Dinner is served. See you at the airport.

Rachel Cusk

(Photograph omitted)