Luis Silveira’s ‘Ensaio de Iconografia das Cidades Portuguesas do Ultramar’, published in the 50’s, is a fundamental source for the study of urban form in former Portuguese colonies. This is an often cited work and its images have been abundantly used. Nonetheless, it has not been analysed and considered in itself, as a unique and essential collection of images representing the most important Portuguese settlements outside Europe as well as noteworthy places connected to the Portuguese expansion or colonization periods. It presents a wealth of graphical information on the settlements which can be understood as town or future town centres. More than a thousand figures depict nearly two hundred towns. The second volume is dedicated to occidental and oriental Sub-Saharan Africa. This paper addresses form and content of this fundamental resource for the study of citycentres in the Portuguese ex-colonies – as seen through the eyes of a public official in the eve of the colonial wars.