IT WAS the first Chinese astronaut who finally blasted the myth. The Great Wall of China, declared Yang Liwei, was not visible from the Moon.

Many patriots were incensed. They suggested that his eyesight was squiffy and that future space-voyagers should be subjected to strict ocular tests. But they should not have minded. Even from a tourist’s eye view, the Great Wall is quite simply stupendous. It certainly surpassed all my own expectations.

Soaring and plunging, scrambling and stumbling up forested pinnacles and down plummeting ravines, it would be enough to make anyone — let alone a barbarian invader — pause to take stock. It may not be visible from the Moon (or even be the most salient of the several man-made features discernable from a satellite) but in the space that really matters to us — that which lies inside our heads — it remains a phenomenon. And perhaps this is precisely because the eye cannot see it, or not in its entirety. The wall vanishes off over furthermost horizons, always leading away into lands that remain tantalisingly out of reach.

As I stood there alone on the ramparts last week, feeling the burn of the dry summer wind on my cheeks, I imagined the sentries who had once paced the same lonely promontories, baking like lizards against stone in the summer, frozen insensible by the bitter winter sleets. Eking out an existence on the very edge of their world, they kept watch for any sign of trouble. Then they lit fires of wolves’ dung and sent smoke signals down the line to the nearest garrison help.

But to the Chinese the great wall is seen less as a marvel of engineering than as a symbol of terrible imperial tyranny. Hundreds of thousands were killed in the prolonged, piecemeal course of its building. Legend has it that their bones are entombed within the structure itself.

The wall may have been conceived by Qin Shi Huangdi, the first emperor of China, as a barricade to ensure the strength of his nation, but the appalling human cost of its construction vastly weakened his people instead and, many believe, led to the downfall of his dynasty.

There is a lesson to be learnt. The Three Gorges Dam is China’s most ambitious construction since the Great Wall. Begun in 1992 under the auspices of President Jiang Zemin, it is due for completion in three years when it will generate enough energy to feed the world’s fastest growing economy. But at what cost?

The project has already obliterated the homes of almost two million peasants. Corrupt local officials have stolen their compensation. And worse is still threatened. Experts are warning that it poses a severe environmental threat. As it silts up and ceases to work it could well cause catastrophic flooding.

Chinese tradition says that a flood heralds the end of a dynasty. It all seems very ominous — not least when the project was initiated by a president whose name can be taken to mean “the river soaks people”.

• WHO CARES what gets lost in translation, when there is so much to be gained? China offered a hotchpotch of most helpful signs. “No entry in peacetime,” read a notice across what looked like an exit from the airport. I suspect it was actually the emergency door. “A single act of carelessness leads to the eternal loss of beauty,” said a Forbidden City placard. “No potherb gathering, no handrail surmounting, no striding . . . and no throwing disused things,” enjoined another sign.

  “Please do not spit or piss at random,” implored the custodians of the imperial summer palace. This temple is “filled with a lumbering atmosphere” a wall plaque informed me.

  So I was thrilled to arrive back in London and find The Meaning of Tingo in my mail. This compulsively perusable little book by Adam Jacot de Boinod offers a delightfully useless compendium of strange words from around the world.

  How had I gone on a press trip to Beijing without knowing the word chenyin (hesitating and muttering to oneself) or qiang jingtou (a fight by a cameraman for a vantage point)? But at least I now know that, should I visit Bolivia, I will be equipped with the word for “I was rather too drunk last night and it’s all their fault”. And imagine how enriched a trip to the Netherlands becomes when you hear Knisper! Knasper! Knusper! — the sound of a bowl of Dutch Rice Krispies.

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