Jiuzhaigou is almost a joke it is so beautiful: a magical valley of forests and shimmering mineral lakes nestling among soaring peaks in the Tibetan massif. Gorgeous waterfalls cascade down the mountainsides; streams meander through glossy meadows grazed by herds of ponies. And there's a rich variety of plants and wildlife: this a land of pheasants, reclusive pandas and colourful rhododendra.

Getting to Jiuzhaigou is not easy. It lies in an inaccessible corner of Sichuan province in western China and the journey from the provincial capital of Chengdu takes two days or more by bus. You lurch along spectacular but notoriously dangerous roads which are snowbound for much of the year and in the rainy summer often impassable. Landslides are common and bus-loads are regularly swept into ravines.

Short of time, we hired a jeep for pounds 30 a day. Our driver, Mr Liu, became a good friend. Although only forty, he had the appearance of a wizened chipmunk with a permanent expression of surprise. He had a remarkable capacity for hard liquor.

For a couple of hours out of the city our road rambled though the gentle, domestic Sichuan plain. The first rampart of the Tibetan mountains emerged suddenly from the smog and we started a full day of climbing into the high country.

In Mao's day, strategic industries tended to be placed in inaccessible mountain valleys. For 60 miles we followed a typical example, with smoking factories sitting incongruously among the fields and orchards. These petered out after the cheerful, dusty town of Wenchuan, and from then on we were in unsullied countryside.

We spent the night at the fortified town of Songpan, an old trading outpost. In the past, the region was a wild frontier of the Chinese empire; Songpan swarms with minority tribes, including Moslems who drifted over the mountains from the north. Gaily-clad Tibetans mix warily with the vigorous Han Chinese who control the trade in the valleys.

Part of the fun of visiting China lies in people-watching, and Songpan gave us front row seats. We rubbed shoulders with rugged Tibetan hillmen down with their pack ponies for the market, red-cowled women buying food, watchful traders and curious loiterers.

Our road took us through mellow villages of wooden chalets clustered by mountain streams. Lower down, solid stone farmhouses squatted among their orchards. White tents of nomadic tribes people dotted the hillsides in the high pastureland. Bright prayer flags, often ragged with age, fluttered above the villages and nomads' camps.

Jiuzhaigou's inaccessibility is a boon: it is now an official beauty spot and would be spoiling fast if it were easier to reach. Even so, some basic hotels are appearing outside the entrance to the National Park. As self-styled intrepid travellers, we spurned these to our cost and paid pounds 3 each a night at a primitive guesthouse up the valley.

The best way to explore is, of course, on foot. As a practical man, Mr Liu was shocked by our eccentric insistence on walking. We would round bends in the track to find him waiting solicitiously in case we had tired of this peculiar behaviour. However, he reluctantly drove us to the end of each of Jiuzhaigou's two high valleys, and we walked back down. We passed pools and lakes of wondrous colours - from the lightest turquoise to the richest emeralds, blues and purples - retained by yellow calcium based dykes. Waterfalls and cascades rushed between the lakes, sometimes punctuated by bushy islets and smaller pools. The water and air were so pure that all colours seemed a little unreal in their intensity.

The most famous sites were briefly crowded twice a day when the buses came and went. As the itinerant tourists arrived, entrepreneurial Tibetans did brisk trade in yak-perching fancy dress photo-opportunities.

The Pear Shoals, a shallow cascade some 200 yards wide, gurgles over a pale yellow bed. A rickety walkway crosses it, with pavilions where we sat dreaming and watching the waters bubbling past. At the bottom, the stream tips spectacularly over a wide fall of sculpted yellow stone.

An expedition to Jiuzhaigou involves some hardships. Even the locals in Chengdu, used to years of Cultural Revolution privation, told us that the food was terrible. They were not wrong. The kitchen in our charmless eating-hall was like a Hieronymus Bosch painting, strewn with half-dismembered corpses. Furnaces roared in the gloom and the grinning cooks gobbed with gusto on to a greasy floor.

The area is bitter at night. We shivered under puny blankets despite three layers of clothes - plus walking boots on the night when a rat noisily gobbled all our soap.

From Jiuzhaigou we moved on to Huanglongsi and wound our way through vivid pastures. Shortly after day-break we arrived above a large monastery with early morning smoke and tiny half-yak cattle dotting domestic fields. Then we reached a magnificent col at nearly 14,000 feet and looked out over the view of mountains receding for miles. Mao Zedong and his revolutionaries crossed this range on the Long March in the mid-1930s. They walked and fought their way, ill-clad, ill-shod and ill-supplied, through the wild, inhospitable land to establish a new base in the north, away from Chiang Kai-Shek's nationalists.

"I hear England is just like this," remarked Mr Liu as we gazed. He still looked surprised despite the certainty of his statement.