In the 1870s, Portugal transferred the public works program it was undertaking on the mainland – in which railways played a decisive role – to its African colonies of Angola and Mozambique. In this strategy, the United Kingdom was an obvious partner, given the historical connection between both nations and the geographical proximity between the colonies each country had in Africa. However, British and Portuguese imperial agendas could easily clash, as both London and Lisbon coveted the same areas of Africa. Hence, the initial and apparent cooperation rapidly evolved to a situation of conflict. In this paper, I aim to analyse three instances of dispute between Portugal and Britain about colonial railways in Angola and Mozambique. I will use the methodological tools of conflict resolution analysis in a historical perspective and the concept of track-two diplomacy within the framework of technodiplomacy.