In the literal sense, there was no such thing as "the Silk Road." When we speak of the Silk Road what we are referring to is an ever-shifting network of trade routes that stretched across Asia, connecting Europe and the Mediterranean region to China. However, it's important to note that this term was never used at the time that the Silk Road is said to have existed: it was invented in 1877 by the German geographer Ferdinand von Richthofen to refer to one route identified by the Greek geographers Marinus and Ptolemy, and he used the plural (die Seidenstraßen) to refer to all routes by which silk reached Europe from China. Subsequently the term became popularized by the books of archaeologists and explorers working in Central Asia (principally Sven Hedin and Aurel Stein), who gave the concept of "the Silk Road" a romantic flair. For historians, rather than using the term to refer to an actual road or a singular trade route, we use it as a shorthand way to refer to all the routes of economic and cultural exchange that linked the two sides of Asia. The time periods for which the term applies vary. Traditionally, the Silk Road is thought to have begun with the emergence of the Roman Empire and Han Dynasty and come to an end when it was (ostensibly) rendered obsolete by the European voyages of discovery in the sixteenth century.

The problem with this usage of the term is that it distorts our image of Asian trade. In Asia as everywhere else in the world, most trade was local in nature. The type of trade we associate with the romantic image of the Silk Road - luxurious silks and spices traveling the whole distance from China to Europe - constituted just a small portion of premodern Asian commerce. Only extremely rarely did merchants actually cross the entire distance - there's a reason figures such as Ibn Battuta and Marco Polo are so noteworthy! Most traders remained rooted in their local regions, passing goods along to other merchants further down the line. Therefore, most trade on the "Silk Road" did not consist of luxury goods destined for consumption on the other end of Eurasia, but of basic commodities destined for consumption just a couple hundred miles away. Valerie Hansen's study of miraculously preserved commercial and legal documents dating from 1st-millenium Xinjiang leads her to conclude that "the Silk Road was one of the least traveled routes in human history." (See her The Silk Road: A New History, p. 235)

So the Silk Road concept has presented something of a problem for historians of Asian commerce. Aside from the simple fact that a single Silk Road did not actually exist, it leads us to focus our attention on the long-distance trade in luxuries between Europe and China rather than the internal factors driving Asian commerce. It's more fruitful to instead speak of Asian commerce the same way we might discuss any other kind of commerce. China, India, Central Asia, the Middle East, and the Mediterranean were all linked by networks of commercial exchange. Some of these links were by land, others were by sea. The nature of this commercial exchange, as well as its volume, did not remain static, but underwent significant change over the centuries. For cultural and religious historians, the Silk Road concept has been more fruitful, with the emergence of a large body of research on cultural exchange across Asia and the spread of missionary religions. Here, concept of "the Silk Road" is no problem: it is simply a metaphor for trans-Eurasian interconnectivity.

As a follow up: how prominent was it - would people just know that it led all the way east and west, or was it only merchants? Would locals direct you towards the road if you asked how to get somewhere?

Followup: Were there any cities/ points I could wait at and be guaranteed to meet someone who was travelling on "the silk road" or was it a network of various routes the entire way?