Columbia University: Silk Road Resources for Educators http://afe.easia.columbia.edu/special/silk_road.htm
For most of world history, the center of the world has been east of both Africa & Europe, to the Eurasian heartland and Mesopotamia. It is the Near East & Central Asian steppe that dominates human time lines before history, before rise of Civilization.
The locus of premodern trade routes, empires, languages, art, war and food is found here in the east moving west. The absolute best study is Dr. Peter Frankopan The Silk Roads: A new history of the world http://amzn.com/B00XST7IX2
Dr. Peter Frankopan Twitter https://twitter.com/peterfrankopan & Website http://www.peterfrankopan.com