We present a new visualization method to summarize and present periodic population movement between distinct locations, such as floors, buildings, cities, or the like. In the specific case of this paper, we have chosen to focus on student movement between college dormitories on the Columbia University campus. The visual information is presented to the information analyst in the form of an interactive geographical map, in which specific temporal periods as well as individual buildings can be singled out for detailed data exploration. The navigational interface has been designed to specifically meet a geographical setting.