This article delves into the processes of territorial transformation by foregrounding the material dimension of infrastructure. The entry of the research is infrastructure network design and planning. We will trace the concepts of territorial transformation inscribed into the material layout of large technical systems by analyzing the discourse of engineers and policy makers involved in the conception of infrastructure networks. In so doing, the material politics of infrastructure networks will be studied: How did engineers and policy makers design infrastructure to generate a specific territorial transformation? Moreover, how did technological plans hold the idea that one could influence modernization processes by means of a territorial transformation instigated by infrastructure? The neutral status of technology is thus fundamentally challenged by showing that engineers, in association with policy makers, were essential actors in the planned transformation of the territory as they organized infrastructure networks according to specific ideas relating spatial and societal transformation. The article focuses on two decades after the independence of Belgium (1831), when engineers conceived comprehensive networks of rails, waterways, and roads. The material politics of two major public works initiatives will be analyzed: (1) the centrally positioned railway network that connected all industrial centers within the territory as well as with the markets of neighboring countries, positioning Belgium into Europe as international turntable, and (2) a network of roads and canals in peripheral, so-called unproductive, regions that had to integrate these regions within national borders, and indeed extend these borders, as well as buffer and govern the side-effects and risks generated by the accelerating industrialization in the central parts of the nation.