The role of proximity and distance in inter-urban networks

As the chapters in this book reveal, cities are embedded within myriad network types at multiple scales linking people and places both within and between cities across the globe. These links are uneven, with some people and places more connected than others, depending on their proximity, which is the focus of this chapter. Within and between cities, proximity can be related to geography as well as other dimensions reflecting closeness. For example, consider a close childhood friend you grew up with. Your spatial or geographic proximity would have been fairly close when you were young, becoming more distant if you decided to move away to pursue a career or tertiary studies. However, you may still regularly see each other and communicate via social media, even if you or your friend then get a job in another city. In this instance, your geographic proximity to this friend has decreased, but your social proximity has remained constant, or even increased. In the following sections, we explain proximity as a concept and how different types collectively shape the connectedness of different cities. The above scenario is a simple example of a complex issue that network scientists have tried to examine through the concept of proximity. Understanding how people and places are linked in a multitude of social, economic, political and organisational relationships, across time and space provides insight into interesting research and policy questions. Complex global networks can be segmented to smaller spatial scales, such as the individual, or aggregated to the neighbourhood, city, provincial, national or regional scales. Likewise, networks can comprise relationships within and/or between firms, organisations, institutions and governments; these serve as foundational to the diverse empirical studies approached from a network perspective. Although these can often reveal vast and complex networks, ego networks radiating from individual (that is, node-level) daily social and economic interactions are the building blocks of globally connected systems.