Starting with the example of an inscription left by a visitor in a cave on the Indian Ocean island of Socotra in 258 CE, the chapter traces the steps of his journey from his native city of Palmyra, Syria. Underlining how transport and exchange of high value, low weight commodities was a main motivation for undertaking long journeys in the ancient world, and how environmental differences created demand for such products, the chapter goes on to discuss the role of topography and climate in shaping long-distance connectivity into macroregional circuits of exchange. These circuits, however, were in turn made up by agglomerations of places and microregions. Taking one of these, Cyrenaica in present-day Libya, as a first example, it is argued that each microregion can be conceived as a network cluster, connected to the overall structure through gateway settlements. The next example is the western Indian Ocean/Arabian Sea, where dispersed hinterland regions were connected by coastal and trans-oceanic contacts into a small-world network structure. The example of movement of commodities between South Asia, Central Asia and East Asia is then used to show how series of such networks integrated the Afro-Eurasian world, but that the friction caused by seasonality affecting harvest times and movement served to reinforce the role of cities placed at the intersection of regional networks as places of exchange.