BY THE time I got to Irkutsk, my hair felt like cold spaghetti. I’d travelled four days and 4,800km (3,000 miles) all the way by train from Moscow. With no showers. The Trans-Siberian continues to Vladivostok, 4,800km farther down the track, but I got off in search of soap and hot water.

Tsar Alexander III understood the importance of uniting the huge Russian continent when he agreed to the Trans-Siberian in 1891. The new railway would open up vast tracts of mineral-rich land beyond the Urals, conveniently take convicts to Siberia, and enable the swift movement of troops to the Amur region which was under increasing threat from the Chinese.

A hundred years ago, when the first through trains started running to Vladivostok, the brochures depicted marble baths, gymnasiums and even a darkroom for developing photographs. The reality was different: breakdowns, no restaurant and frequent broken rails.

Today the conditions are somewhat better. The Trans-Siberian is no tourist train. It’s usually booked solid and provides a vital service for Russians, Mongolians and Chinese who can’t afford the plane. I shared a four-berth compartment in second class, which was comfortable, if cramped. The lavatories are like those on a train in the UK — but if you’re thinking of washing, forget it. There areshowers only in some first-class compartments.

I’d had nightmares of drunken soldiers and babushkas with bags of smelly food, but two of my compartment companions turned out to be English. Duncan and Christine were great company and we became firm friends during the four days on board. The first night we sat on the two upper bunks and chatted late as the train swayed and clattered along, a bottle of vodka encouraging friendship.

I woke late to find a brilliantly sunny day. The train was rattling along. Outside, big industrial skylines had given way to green rolling hills dotted with wooden huts, each with a wisp of smoke curling up from the chimney and a garden of carefully spaced vegetables.

Every couple of hours the rattle and sway was broken by a station stop. On the platform, food was hawked by all and sundry: khaki-coloured smoked fish the size of your thigh, little plastic bags of blini — Russian pancakes which tasted surprisingly good — fruit, vegetables and biscuits. Kiosks on the platform sold drinks, sweets and cigarettes. For ten or 15 minutes we bumped up against life in the middle of Siberia, and then, in an instant, left it behind again.

The time passed strangely quickly. Corridor friendships were struck up swiftly and the routine of the train took over. Everything takes longer in the cramped compartment: getting up, eating a picnic lunch, finding a book — a whole sequence of “Could I just put my foot here so I can get my bag?”; “Can I borrow your bottle opener?” And it works just fine. Four days is enough to find plenty to talk about without discovering the quirky habits that start to grate over a longer period of time.

In the evenings we dined in the restaurant car. At the Paris Great Exhibition in 1900, the Russian Government put on a lavish display featuring a full mock-up of the Trans-Siberian’s restaurant car with mahogany panels and extravagant menus.

Each night our grumpy waitress with the bad bleach and perm-job would drop the menu on the greasy tabletop. Inside its bashed cover, dishes were listed in Russian, English and German. On the first night we realised the choice was far more limited. It was any of the four things that had prices scrawled beside them. After this we adopted the Russian technique of ordering beers, feigning disinterest and trying to catch her by surprise by suddenly asking what food there was.

We reached Irkutsk at 3am Moscow time on the fourth day. Except my watch said that it was 8am. Since leaving the Russian capital we had crossed five time zones. This time warp is more subtle than jet lag and quite disorientating — and just to make things really confusing, the train and stations all across Russia run to Moscow time.

After a stop in Irkutsk, I boarded a train for Ulan Bator, the capital of Mongolia. We passed some of the trip’s most impressive scenery soon afterwards. Lake Baikal, the world’s deepest freshwater lake, home to hundreds of unique species including freshwater seals, was dazzling.

Huge blocks of ice on its surface made the sunlight bounce crazily back and forth. Most of the railway was built by gangs of convicts with nothing more than picks and shovels and this was some of the most difficult terrain, requiring more than 200 trestles and bridges and 30 tunnels. Prior to 1904, trains had to be loaded on to boats to cross the lake. The trip was particularly unpredictable in winter when thick ice often marooned the ships in port for weeks at a time.

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