I've written about China's mag-lev train a couple of times, but it's another train altogether that's making headlines this week: The newly opened Qinqhai-Tibet Railway that links the Tibetan capital of Lhasa with the rest of China. There is now, for the first time, a direct rail link from the national capital, Beijing, all the way to Lhasa, although you can expect to spend 48 hours on the train to make the journey.

Outside China, the train is controversial, with many reports commenting on its potential to bring a flood of new Han (China's ethnic majority) migrants into Tibet, possibly risking the plateau's unique culture. Inside China, where coverage is somewhat circumscribed, it's the achievement of constructing the world's highest train--much of it at altitudes over 4,000m--and the necessary technological wizardry that are getting covered.

Hu greets the master technologists.

The train had to overcome two challenges. First, it was built across incredibly rugged terrain, including earthquake-prone areas and a broad stretch of permafrost on the high plateau. Second, with Lhasa at about 5,000m, the train had to deal with some of the same challenges as airplanes do, including thin air and high radiation.

Two articles in China's state-run English language newspaper, the China Daily (which also supplied the photo above), discuss the various technological aspects of the train. The first covers the problems of altitude, and notes that the train has two oxygen systems: One that infuses the air inside the carriages with extra oxygen and one that can supply individuals who are in distress. Think this is overblown? Think again. When my wife and I were at Lake Karakul in China's far west a few weeks ago, at a relatively paltry 3,500m, my wife suffered severe headaches and nausea that had to be relieved by supplemental oxygen until she acclimatized. Even I felt crabby and headachy for much of the time we were there, although that might just be me. The train also has windows specially coated to resist the strong ultraviolet radiation at that altitude.

A second article covers the challenges of building on the permafrost. It reports that preparatory work started four decades ago. Like the Three Gorges dam, this seems like a project a long time in the making. Interestingly, one of the main problems the engineers have had to take account of is the risk of global warming, which might soften the earth upon which the railway sits. Monitoring systems will watch the ground and elevated tracks will keep large stretches of rail away from unstable ground. Despite all this, the railway ministry claims the line will be "harmonious with the ecology". If so, that would be an industrial Chinese first.

Ecological doubts aside, it sounds like a pretty miraculous train, and there is probably some staggering scenery on the way. Still, I live in Beijing and two days is a long time on a train, even a technologically advanced one. I might still fly instead, and spend my precious vacation days in Tibet itself rather than on the train.

Udate: Jane Macartney, the China correspondent for the UK's Times newspaper, has been blogging about her experiences on the train. Her latest entertaining and slightly spooky post is here.

Update 2: Peking Review has an excellent post on the achievement the train represents, and what it might and might not accomplish.

Welcome to Tibet!