The Silk Road is an ancient trade route linking China to Imperial Rome.  Also called the Silk Route the Silk Road was about 6,000 kilometers long, or about 4,000 miles.  The various routes of the Silk Road  stretch from the Chinese capital Changan, across the Chinese plain of the north , through the pamirs and the Karakorum range to Samarq and Bactria, to Damascus, edessa, and the Mediterranean ports of  Antioch and Alexandria. 

        The Silk Road first started to be in use at about 100 b.c , after Chinas emperor Wu Ti from the Han dynasty conquered large sections of Central Asia .  The new areas stability, and extensive road building, enabled caravan traffic to go vast distances, which carried high valued goods. Some of those goods were silk, wool, gold , and silver. Caravans generally stopped on the roads and traded goods, rather than traveling the entire route.
  Ideas and thoughts also traveled threw the roads some of the ideas were Nestorianism, a sect of Christianity, which were introduced from Europe and later, Buddhism traveled from India to china. 

        The silk road fell when the roman empire The silk road fell when the roman empire disintegrated in the 5th century, and safety conditions that deteriorated after some nomadic tribes came to control sections of the route. Also  Under the Mongol empire in the thirteenth century, Italian merchant Marco Polo traveled to China by the Silk Road, and the trip he  took was about three years long.