This train was packed with Mongolian traders, the compartments bulging with boxes. Fish paste, mechanical valves, moisturising lotion, booze, fags and all manner of clothes spilled out into the corridors.

To avoid customs, traders hide stuff everywhere: behind bulkheads, in underfloor compartments and behind ceiling panels. Boxes of clothes were broken down into smaller packages to stash away. In the corridor people painstakingly threaded electrical wire down the length of the carpet.

Ulan Bator was a fascinating concoction of ex-Communist drabness and Asian dynamism. Brand new Toyotas jostled for space on the roads with bashed-up old Russian Volgas and Ladas. Stalinist architecture stood crumbling in faded grandeur alongside shiny new office blocks.

On my one night there, I visited the state theatre to hear Mongolian throat singing. A little rotund man creased his brow, opened his mouth and emitted a strange buzzing noise from deep in his chest. The tone rose to a high-pitched gurgle that oscillated and vibrated. It sounded as if he’d swallowed a Jew’s harp.

The next day, it was a hot ride through the Gobi desert to the Chinese border. The greenness of the steppe turned to brown, then yellow as we hit the vast desert. Herds of gazelle bucked and bounced, dashing away as the train rumbled past. A night of interrupted sleep followed as we crossed another border.

To make the process more laborious, the track gauge in China is different. In one of the most technically complex manoeuvres I’ve seen, the whole train was shunted into a huge shed, the coaches uncoupled and massive hydraulic lifting bars inserted under them. They were lifted up as the bogies were swapped underneath and the carriages slowly winched back down. For the three hours this took place, we had to stay on board and the loos were locked.

The next day we ploughed on through China. Beside the tracks people toiled in conical straw hats in the sun, irrigating and planting. Early afternoon, the train began the long wheezing climb up the mountain range that’s crested by the Great Wall. There is time at the top to admire the views, as another loco has to be attached to help brake the train down the steep descent. The time seemed to speed up as we clattered on across the plains to Beijing. My compartment companions and I talked non-stop, realising that after living in each others’ pockets for nearly a week, we’d soon be going our separate ways.

Finally, suddenly, we were there. We struggled to re-pack rucksacks, swapping books, exchanging email addresses and dumping the junk we’d accumulated. I left the compartment last, taking a final look around. After thousands of miles and six time zones, my body was tuned to the constant swaying of the train. For days after I got off, I still felt the rhythm of the rails under my feet. I also spent a lot of time in the bath.

Page 2: need to know
Page 3: how to survive the train

()Need to know

Getting there: Jeremy

Head travelled with Global Village (0870 4424845, www.globalvillage-travel.com), which offers two-week trips from Moscow to Beijing through the tour company Russia Experience, from £1,085. The trip includes two nights in a Moscow hotel with half-day sightseeing, accommodation in Irkutsk and Mongolia, some meals and Russian and Mongolian visa handling. More “bare bones” trips can be arranged from £509.

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