This article explores the uneven patterns of topographic mapping of colonial Northern Rhodesia (today Zambia). These patterns were generated in the years 1927–1931 and have an enduring effect today. Previous accounts describe colonial mapping in Africa as ‘incomplete’, but this is an inadequate conclusion. The article proposes that these unsatisfactory narratives of cartography can be corrected by applying the model of a cartographic economy to the close reading of archival sources. This model is used to interrogate topographic unevenness within the framework of the interests of diverse parties, with differing values and resources. It reveals that the patterns of topographic production were particularly strongly linked to aerial photographic projects. These projects documented areas that were preconceived as valuable. However, the article reveals that the cartographic economy was determined by more than just the value of the land, as the value of the cartographic representation itself could be manipulated independently. This perspective should be considered in the study of British mapping of other colonial territories.