This volume approaches the topic of mobility in Southeast Europe by offering the first detailed historical study of the land route connecting Istanbul with Belgrade. After this route that diagonally crosses Southeast Europe had been established in Roman times, it was as important for the Byzantines as the Ottomans to rule their Balkan territories. In the nineteenth century, the road was upgraded to a railroad and, most recently, to a motorway. The contributions in this volume focus on the period from the Middle Ages to the present day. They explore the various transformations of the route as well as its transformative role for the cities and regions along its course. This not only concerns the political function of the route to project the power of the successive empires. Also the historical actors such as merchants, travelling diplomats, Turkish guest workers or Middle Eastern refugees together with the various social, economic and cultural effects of their mobility are in the focus of attention. The overall aim is to gain a deeper understanding of Southeast Europe by foregrounding historical continuities and disruptions from a long-term perspective and by bringing into dialogue different national and regional approaches.