Development of transportation infrastructure has long been seen as a fundamental tool in shaping cities, and vice versa. However, moving beyond the discussion on the causalities of transportation infrastructure and urbanization, various authors have criticized large scale infrastructural projects for promoting injustice and reinforcing social and spatial polarization by supporting profit-oriented developments. Contributing to this line of thought, this study examines the wider socio-politics of the transportation -urbanization nexus in large scale infrastructural projects associated with urban development in two case studies in the department of Antioquia in the North-east of Colombia. It focuses on the relationships between these projects and urban development approaches and policies, addressing the socio-political benefits and profit-oriented interests of hegemonic population groups, and how infrastructures embody specific forms of power and authority of these groups. The analysis mobilizes a combination of the theory of technological politics and a strategic-relational institutionalist approach, which draws attention to the momentum of large-scale sociotechnical systems, and to the response of modern societies to specific technological imperatives. This paper shows through its two case studies how the causalities of transportation (infrastructure) and urbanization are embedded in wider social, political, economic and cultural dynamics. As such, the paper shifts the focus to the relationships between actors and their interests, transportation (infrastructure) and socio-politics, and the ways in which transportation infrastructures and their techno-political frames possess deeply embedded socio-political qualities, include means of power and authority, and may favour specific actors and interests.