China was first known in the West as Seres, the land of silk or serica. The Romans were entranced by this strong but delicate thread, and believed it was combed from trees. But it was also viewed as a decadent, effeminate luxury -- for the appetite of Rome's better classes for silk was rarely sated, and without a luxury (other than glass) to export in return, silk imports emptied Rome's coffers. As a result, in A.D. 14 the Roman Senate forbade the wearing of silk by men, and Caligula, who was fond of diaphanous silk garments, was disparagingly referred to as Sericatus.

In Tang China, silk was the most important form of legal tender; taxes, fines, and officials' wages were all measured in bales of silk. Silk was used to buy off raiding armies of Uighurs and Tibetans and (it was hoped) make them a bit less barbaric.

The term "Silk Road," coined in the 19th century by German geographer Ferdinand von Richthofen, is both an evocative and misleading appellation. The trade routes that connected China and the West from the 1st century B.C. until the 10th century A.D. carried a whole inventory of luxuries and necessities beyond silk, from gold and jade to wool and rhubarb. Nor was the road traveled from end to end. Chinese merchants rarely went beyond the edges of the Taklamakan Desert before turning the goods over to Sogdian or Parthian caravans, who were left to face the forbidding mountain passes of the Pamirs. Only devoted missionaries went farther, like the legendary monk Xuanzang, who spent 15 years traveling across India and central Asia in search of Buddhist sutras.

Silk was just one of many goods transported over these vast distances. Apricots, peaches, and pears reached the West, while China gained the fig tree and the grapevine. China imported spices, woolen fabrics, horses for military campaigns, and foreign novelties such as musical instruments, coral, colored glass, and jewels, which fascinated the courts.

Traders also brought foreign ideas, and were soon followed by missionaries of many faiths. Nestorian Christianity, Zoroastrianism, Manichaeism, and, most significantly, Buddhism, were welcomed by a confident and cosmopolitan civilization. Doctrines and art spread eastward, leaving spectacular monuments in the cave temples of Dunhuang, Mai Shan, and Kizil.

The Silk Road wasn't one road at all, but a series of routes emanating from the capital of Chang'an. From Chang'an, camel trains would follow the Wei River west before branching into several different routes.

The southern route passed through Dunhuang, Miran, and Khotan, in the shadow of the mighty Kunlun Shan, whose meltwater streams fed thriving Buddhist communities. Intrepid travelers today, tolerant of bare-bones transportation and accommodations, can still traverse the route, which will lead to bustling towns such as Khotan with ancient markets and traditions little disturbed by either tourism or modernization.

The middle route was initially (1st c. B.C.-4th c. A.D.) popular, allowing merchants to float on barges down the Tarim River from the garrison town of Loulan to Korla and Kuqa. But when the river changed course, and Lop Nor Lake "wandered off," this route was abandoned. Thanks to more recent nuclear testing, which finally ended in 1996, this route will likely remain closed for the half-life of plutonium.

The northern routes, skirting the northern and southern foothills of Tian Shan (the Heavenly Mountains), were menaced by Kazakh and Kyrgyz bandits. The bandits are less of a problem these days, and most travelers follow the northern route along the He Xi corridor to the mighty fort of Jiayu Guan, the peerless Buddhist caves of Dunhuang, and the grape trellises of Turpan. Beyond, the road leads to fascinating oasis towns such as Kuqa, and the great market town of Kashgar, skirting the northern edge of the Taklamakan Desert. (Taklamakan is commonly translated as "go in and you don't come out," but in ancient Uighur it means "vineyard," evoking a time when the region was more fertile.) The desert dunes have been marching south for many years, threatening the oasis towns of the ancient southern route.

The present character of the Silk Road is Islamic rather than Buddhist. An exodus of the Turkic Uighur peoples from western Mongolia displaced the Indo-European inhabitants, the Tang dynasty fell, and Islam gradually spread east through the Tarim Basin. With the rise of sea trade, land routes fell into disuse. Settlements and temples (which also functioned as banks) were abandoned to the desert. They remained undisturbed until the turn of the 20th century, when archaeologists from Britain, France, Germany, Russia, Japan, and (later) America came searching for lost Buddhist kingdoms.

The adventurers saw the Han Chinese as fellow colonizers, keeping the Turkic Uighurs in their place. British diplomat Eric Teichman believed "the Turkis are a patient, contented and submissive people, made to be ruled by others." Xinjiang means "new territories," rather a giveaway in itself, but many Han guides will try to persuade you that this region has always belonged to China. Turkic Uighurs make up the majority of the population in Xinjiang, but they are gradually being displaced by a wave of migrants from the east. After an absence of over a millennium, Han Chinese are reasserting control over the Silk Routes with a ruthlessness that the Wudi emperor (reigned 141-87 B.C.) -- the first ruler to control the Silk Routes -- would have envied. Most Uighurs would prefer to rule themselves though, a fact which is becoming ever clearer in the increasing tensions in Xinjiang. Fatal attacks on police in Kashgar and Kuqa in 2008 were followed by full-scale riots in ?rumqi in July 2009 that left over 150 Han Chinese dead. The army was sent in, curfews were imposed, and on the surface (at the time of writing) things appear to have calmed down; however, the local Uighur population is growing increasingly resentful of what they see as the Han Chinese occupation of their land and the situation remains tense. Check travel advisories for the latest before you plan a trip to Xinjiang.

Travel along the Silk Routes has always been arduous, temperatures are extreme, the distances involved are considerable, and it's very dusty. Peak season is early May and mid-July to mid-October. Outside of Xi'an, Lanzhou, Dunhuang, and ?rumqi, expect little in the way of luxurious lodgings. The more adventurous should seek out the Uighur trading centers of Kashgar, Khotan, and Kuqa, or (if they remain open to foreigners) the Tibetan monastic settlements of Xia He and Langmu Si. Note: Unless otherwise noted, hours listed for attractions and restaurants are daily.