Ibn Battuta's Travels
A young legal scholar left Tangier for the pilgrimage to Mecca and did not come home for twenty-nine years. Ibn Battuta covered perhaps 75,000 miles — West Africa, East Africa, Arabia, Persia, the steppe, India, the Maldives, Sumatra, China — and worked as a judge in several of them, because a shared language of law and faith meant a Moroccan could hold office in Delhi. His account is the best surviving portrait of the 14th-century world from the inside. He complains about the food.
The path or medium of exchange moves, and a place or power rises or declines because it sits on or off the new route.