A young man in a white skullcap brandishes a long knife. He's beckoning us to notice his chrome, cross-shaped machine - part Middle-Ages torture implement with sharp points and a hefty screw, part useful tool - and the rich crimson liquid bleeding into a red bucket below it.

He's got bottles of the stuff already filled, and just as we are about to shudder and turn away, we realise he's squashing the ruby juice from pomegranates. 

This is the Kashgar Sunday market, on the far western border of China, and high point of the week. The locals dress up for this, hook the family donkey to the cart, then pile on and head for town.

The place is absolutely bursting with people. They come for the food - mounds of figs, cartwheels of bread, baked sheep's heads, pomegranates - the energy, and the socialising. It was hard to imagine that a thousand years ago (and a thousand years before that) this place would have been just as busy.

The saga of the Silk Road is a long and complicated one, the story of a hapless scout that spent more time in gaol than research, a mystery fabric craved as much for the manufacture of pennants as petticoats, and a trade route that flourished, then foundered.

The Silk Road covered thousands of kilometres from Xian in the east (itself 1165 kilometres west of Beijing) with several routes branching north, south and central, seeking mountain passes and safe passage, as the caravans were often threatened by robbers, and skirting the worst of the deserts before striking out over Central Asia and branching again, north and south.

The world's rarest and most precious commodities passed this way, and the travellers also traded knowledge, culture, religion, and bloodlines. Born in mythic times, in the end it gave way to simple economics - ships of the sea over ships of the desert.

Yet when I saw bolts of flamboyantly coloured silks in the markets, I was dubious, for much has changed. Today's travellers are clad in polyester; China's beasts of burden are black smoking Dong Feng lorries, their blue paint chipped; and the oases are petrol stations where the tarpaulin covered ships of today's desert, refuel.

We spent three weeks playing polo - that's Marco Polo, you understand - down the same trails he explored in the 13th century from Kashgar in the west to Xian in the east. He returned with amazing tales of tiger and oil wells. We came back to amaze our friends with tales of 3000-year-old mummified bodies preserved by desert sands and now displayed in glass cases in a museum at Urumchi, and Turpan, the world's second lowest city, with its brick raisin drying lofts.

We had tales of Buddhas cut 27 metres tall into the rock at the Binglingsi Thousand Buddhas Caves, and my personal story of a gentle monk at a mountaintop monastery who shyly pressed a sheet of densely written and complexly folded prayers into my hand.

We traded too, bringing back trophies of shawls and purses, and a miniature terracotta warrior from Xian, made, they said, from the same earth being dug out from around the full-sized warriors in the massive pits beside the gift shop. We were in luck too. The fortunate farmer on whose land all this had been discovered, signed for us a book about the diggings. 

But to understand this epic route, you must learn it by length and breadth, for the history is as exciting as the geography.

The process for making silk itself is reputed to have been devised by Lei Zu, wife of the mythical Yellow Emperor, said to have ruled around 3000BC. Over the ensuing centuries in China it was used for clothing and flags, and of course, export.

During the Han dynasty, in the second-century BC, Emperor Wudi sent an emissary, Zhang Qian, to explore the routes to the west of Chang-an (now Xian). Silk was possibly the last thing on his mind. He was after security and defence recruits.

Zhang was soon captured and, word has it, spent a decade in gaol before escaping, pressing on and reaching Kashgar. On the return trip he was again captured, only finally returning to Chang-an 13 years later.

However the trail had been blazed and his tales of the journey and the legends he had heard of other, further, lands - some say as far west as Rome - gave the emperor the courage he needed.

For the next 1400 years or so, this would become the route for all sorts of precious things - ivory, gemstones, coral, gold, and textiles from the west; furs, ceramics, bronze, and of course silk, from the east.

Food travelled too - ginger, rhubarb, cinnamon. Millet and mulberries from China, and peaches, dates grapes, and nuts from the Middle East and Europe.

Naturally, as the travellers met and mingled at the various stops along they way, they did more that trade. Ideas were exchanged, they shared artistic processes, and cultural ideas rubbed off. Buddhism spread easily along the Silk Road (which interestingly was first called this in the 19th century by a German scholar, Baron von Richthofen) and many ancient carvings and art remain.

Yet the importance of this route collapsed quite suddenly. Finally the European courts who coveted silk for flags and fashion, cracked the process for making it themselves. The climate was changing in western China, too, with many oases drying up; and of course the sea routes from Guaghzhou to the Middle East became established, creating a more cost-effective means of transport.

Today the Silk Road may not be used as much for commerce and international trade, but its attraction lies in the changing faces of its people, and the history locked often deep in the sands.

So this was our purpose as we flew five hours from Beijing to Urumchi to begin our long trip east, mimicking Marco. Playing Polo. He returned wide-eyed with all he had seen, and so did we.

At an altitude of three thousand metres, we were led to "Little Tibet", Xiahe in Ganzhou province with its authentic lamasery (monastery) one of the largest in the country, with its treasure of relics that include 60,000 volumes of Tibetan scriptures. And although we felt vastly separated from what we now call Tibet, we discovered that this is the eastern extremity of the Tibetan plateau.

Here we watched a colourful temple ceremony involving deafening and mournful horn music as hundreds of monks in maroon cloaks and knee-high felt boots congregated on the steep stairs before kicking off their boots and filing inside for the ceremony.

At other places we discovered markets where silk was almost lost amongst towers of embroidered hats, cartloads of watermelons, shoes, fans, handbags, paintings and spices - and, tragically, fox and cat skins and pelt after pelt from dozens of endangered species.

We saw mosques minarets, and minority people in traditional dress, underground burial tombs still being excavated.

At Xian, those terracotta armies in the walled city awed us, of course, but a lesser known display of Lilliputian figures from recent excavations nearby at Hanyangling, was just as enthralling. And as we looked at the hills surrounding the area - many of them that same humped shape that had been the clue to the warrior's tomb - we realized that this place must have so much more to unearth.

At Crescent Moon Lake near Dunhuang, we discovered an unexpected oasis amongst the towering Sahara-like Mingsha dunes. Camels sat ready for use as transport or as a photo-op, while other people scrambled the steep "singing sands" to a view they would never forget.

The two ancient and deserted cities of Jiahoe and Gaochang showed us only crumbling remains of 2000-year-old cities abandoned to the desert winds, yet the ghosts of the life that once filled them were still present.

Then, days later, we encountered the intact fortifications of Jaiyuguang Pass at the western end of the Great Wall, known as "the Impregnable Pass Under Heaven".

Always changing, the Silk Road is as fascinating today as it was a thousand years ago.

And I can almost hear Marco Polo agreeing with me.

FACTFILE:

The Ancient Silk Route extended 7000 kilometres from Xian into Central Asia, India, and Syria, and continued from the second century BC to the 15th century AD.

Getting There: Helen Wong's Tours (www.helenwongstours.com) offers fully escorted 26-day tours covering the entire 4000 kilometre length of the Chinese portion of the Ancient Silk Route, which includes air travel from Australia and all accommodation.

To do similar: Fly to Beijing then Urumchi with a side-flight to Kashgar - it's too far to drive. Self-driving in China is difficult, as most road signs are not written in our script, so for the trip from Urumchi to Xian you should hire a car and driver and an English-speaking guide.

Accommodation: There is a full range of accommodation in China from basic to quite comfortable three star in smaller more remote towns, and luxury five star in the larger cities.

Getting around: Trains may be "hard", or "soft" with sleeper accommodation. They are usually a quick and comfortable way to travel.

Best time to go: April to October. The climate varied from harsh desert to mountains, and conditions change rapidly, so pack accordingly.

Food: Do not drink tap water. On the Silk Route the food varies enormously from west to east. In Urumchi and Kashgar Muslim meals are mutton based, becoming spicier with other meats as you travel east. There are Tibetan restaurants in Lanzhou and Xiahe, then around Xian, dumplings and Cantonese foods.

Currency: There are approximately 6.3 yuan renminbi (RMB) to the Australian dollar. Tipping is now more commonly practiced. Allow between $3 to $5 a day for drivers and guides.

 Visa: Australian citizens are required to have a visa for travel in China.