The quantity of archaeological data for the fortified hilltop settlements of the Late Intermediate period on the Andean altiplano, called pucaras, varies greatly. Some areas, such as the territory of the Colla Aymara chieftaincy east of Lake Titicaca, are well documented thanks to recent and exhaustive research. Other areas, such as the territories of the Lupacas and the Pacajes, are much less documented. From comparative spatial analyses of satellite images from these two territories, we obtained new data on pucaras, whose characteristics seem to differ from those proposed in the archaeological literature. Through a combination of fieldwork and spatial analysis of 295 pucaras, we identified 252 unpublished sites and propose a new typology comprising four categories. Based on ethnohistoric data and the results of the architectural and geographical analyses, we discuss the possible motivations for building so many pucaras; we suggest that some reasons are of a symbolic nature.