The largest and best known of these is the trans-Saharan trade network, which “extended throughout the Sahara Desert, an expanse of 3,320,000 square miles” (Schraeder 2004a:36). “If you traveled across the United States from Boston to San Diego, you still would not have crossed the Sahara,” explain Marq de Villiers and Sheila Hirtle in a captivating history of the region, “and if you started from Paris you’d be at the Urals, deep into Russia, long before you ran out of Sahara”
This is an example of a centralized state described in this section of the text, also known as the "Trans-Saharan trade Network.