Saving the Great Wall of China

As I clamber across the rocky terrain in my Goretex North Face hiking boots I notice that my guide, Sun Zhenyuan, is wearing cheap cloth slippers with wafer-thin rubber soles. "I wear out a pair every two weeks," he says. I do a quick calcula- tion: Over the past decade, Sun has worn out some 250 pairs of slippers trying to protect the Great Wall - and to preserve his family's honour.

More than four centuries ago, Sun's ancestors arrived at this hilly outpost in northern Hebei province wearing military uniforms and, presumably, sturdier footwear. Soldiers in the Ming imperial army, they were tasked with defending this section of the Great Wall (which the Chinese call changcheng or "long wall"), nearly 6,500 kilometres from where it begins in China's western deserts - and 65 kilometres from where it plunges into the Bohai Sea

Twenty-one generations later, Sun is carrying out the same mis- sion: defending the Great Wall against invaders. A wiry 60-year-old peasant in a faded Mao jacket, he has invited me to join his daily patrol searching for fresh damage inflicted by tourists and locals to the stretch of wall on the ridge above his home in Dongjiakou village.

As we near the top of the ridge, the Great Wall looms above us, a 10-metre-high stretch of rough- hewn stone topped by a two-storey watchtower. Sun is eager to show me why he wills himself up the moun- tain every morning for his patrol. When we reach the tower, he points at the Chinese characters carved above the arched doorway: Sunjia- lou, or Sun Family Tower. "If you had an old house that people were damaging," Sun asks, "wouldn't you want to protect it?"