This collection of articles combines a set of works that study the contribution of transport infrastructure to the process of state building in different countries in Western and Central Europe. The focus and the themes treated vary, but have two common denominators: firstly, they are based on either completely original, or previously little-used, primary sources; and secondly, each work reveals new ways of interpreting how transport networks have shaped the territories into which they were introduced. Each article is an example of the wealth of potential approaches available and also helps us to interpret the processes involved in state building, which are a necessary precedent to European Integration (EI). To put the seven works that make up this special issue into context, I shall start this introduction by examining three aspects that complement them. I shall firstly clarify what we mean by EI. Secondly, I shall examine whether EI processes existed prior to the creation of the institutions that were set up after World War II to promote integration. Then, thirdly, and finally, based on the previous analyses, I shall look at the emergence of a railway network in Europe and the role that the European states played in this process. The fourth section will present the articles.