The goal of this study is to apply the extraordinarily rich set of historical cartographic and remote sensing data of Cairo, Egypt to the analysis of the problem of informal development in the twentieth century. Remote sensing of urban areas has been dominated in recent years by multispectral analysis of Landsat imagery. This restricts studies both temporally and in spatial resolution. In this study an aerial photo interpretation methodology is applied to images and maps spanning two centuries of Cairo’s history at a spatial resolution on the scale of individual buildings. From these techniques insights can be obtained of the political and social forces shaping the development of Cairo.