In 100 years, perhaps, the far west of China will be linked to Xian via bullet train, but for the present one makes do with a diesel making its slow, unhurried progress through an endless desert.
The line passes just north of Turfan, the second lowest place on Earth, where centuries of irrigation still manage to keep the sand at bay. And Jiaohe, the ruined capital of the Uighars, lying at the confluence of two rivers, an unsung wonder, a dead city where you fear getting lost in the empty streets.
You need a good deal of patience: the toilet is broken, the windows jammed, but the sound system is perfect. The effect is not unpleasing: a mixture of potted local history in soft Mandarin with the latest hits from the south. Try to imagine travelling very slowly from Edinburgh to King's Cross, and being regaled at Nottingham with a potted version of Robin Hood. And Whitney Houston? Does she know they use her as background music on the Xinjiang line?
The notice by the window contains dire warnings about the carriage of dangerous goods: it would seem the locals have taken to transporting dynamite and other fireworks under their bunks with catastrophic results. Not often your bags are X-rayed on entering a railway tunnel. You feel safe, though.
As usual, getting tickets was a minor miracle. China runs on whom you know: no connections, no pull, no hope. Tickets are like gold, never within reach until the day before and then you should have asked yesterday. Look on the bright side: lots of people are given lots of chances to make lots of money, and the longer the chain, the better the distribution of wealth. And then, of course, something somehow must always remain for the party bigwig, who may or may not appear. Did someone say "classless" society?
In Urumqi, there were two large halls for the hard-pressed proletariat but a "soft" reservation brings plush settees, subdued lighting and decor well beyond what BR could ever afford. And behind a curtain lies another room.
Out on the highway further west, on the old Silk Road (although anything less silken would be hard to imagine) traffic builds month by month, as China starts to develop the Taklamakan, that dreadful desert between the Mountains of Heaven and Tibet. They will tell you there is more oil here than in Saudi Arabia but no one is really sure. Things will move slowly, of course, but the signs of development are everywhere. Oil derricks now stretch out to the horizon. Driving engenders a mixture of enthusiasm and despair. The beauty of some stretches, the long spectacular gorges west of Toksun and the fiery hills north of Turfan, the blacks, browns, yellows and reds with a sharp line of snow where the mountains meet the sky, is tempered by the certainty that round the next bend will be the wreck of a bus, a burned-out trailer, or an abandoned car. A highway designed for heavy traffic in both directions, but with a crown so high and the edges so unpredictable that everyone hogs the centre line. And the remains of slight misjudgements are strewn like litter on the road.
Life survives on the rim of the desert, fed by streams that run a few miles, do their duty to man and then die in the sand and the heat. All the more shocking, then, to discover pollution in such a place. On the train, everyone just throws everything out with studied nonchalance, and apart from the ominous little twists of sand and dust that rose into the air outside, nothing moves and no one complains.
Fertiliser, mineral extraction, you name it: there is a factory belching smoke into the once-pure desert air. Travelling east from Toksun gorges is a vast plain covered with clumsy smudges, long low threads of smoke from factories in the middle of nowhere. Worst of all is Urumqi itself, sitting in the bowl in the hills to the north of the Mountains of Heaven. By 9am on a windless day a brown soup fills the bowl and gridlocks can last for ever. Travel the 60 kilometres to the Heavenly Lake, a piece of Switzerland under Bogda Feng that rises 5,570 metres into the snow, and it may well take you four hours in a constant stream of traffic.
Where will it end? To imagine the Chinese with one car to a family is surely to picture Armageddon. Could it happen? Well, three years ago no one would have imagined private taxis in such numbers, but the man who drove us to the station had borrowed money to buy his little car for cash and had proceeded to pay off the loan in less than a year; now he is earning more in a week than a university lecturer earns a month.
They make Volkswagen Santanas in Shanghai, but what of all the Audis and Benzes on the road? Is it true that they are spirited away from the streets of Germany, brought across the Central Asian states, where they do not have the money to buy, and sold in Urumqi, where they do?
Travelling in China is still a wearing experience: you must pay upfront, but since tickets are only available from the point of departure you must travel great distances with little bits of paper, names and addresses of who will meet you with the next ticket. It seems to work but you never know. And it keeps you nervous. They will tell you that things have improved beyond measure in the past three years since the cork has been let out of the bottle, but the stewardesses on internal flights still throw cans of fizzy at you, and say "No" when you ask for something. Flights are still cancelled at the last moment and someone forgets to tell the passengers.
And what of the future of this far-flung part of the Chinese state, where the majority of the population professes Islam and speaks a form of Eastern Turkish? The Chinese have been careful to produce a parallel series of administrative structures, so that local groups are made to feel they have a say, and the whole of the province of Xinjiang has "autonomous" status. The sheer variety of ethnic groups -- Uighur, Kazak, Uzbek, Hui, Mongol, Tajik, Xibo, also helps since no one group wants another to dominate. China has a reasonable historical claim to the area and in any case will never let it go as its future might well depend on what lies beneath.
The picture is not entirely rosy, of course. Tension exists and does bubble over on occasions. In the covered markets the Chinese often feel out of place, and in Kashgar they have to be positively careful. All locals speak and some read Chinese, but most of the Chinese I talked to knew but a smattering of Uighur and could not read the Arabic script at all. This did not matter in daily life since all signs are in both scripts, but it did suggest who felt in charge. There is a strong impression, however, that things are on the up and everyone's lot has improved substantially in the last few years. Tibet, just to the south, seems a world away. But why, you ask yourself, why are they buying up so much ex-Soviet hardware and moving it across the border? And why the endless lines of army trucks on manoeuvres?
"Do they speak Uighur in England?" an old, white-bearded man asked as he showed me into a mosque with a Chinese roof. Good question.
Richard Bowring is professor of Japanese at the University of Cambridge and adviser to the Higher Education Funding Council for England on non-European languages.