Maps can be powerful tools of nation building and empire, and therefore powerful historical sources. Whether they delineate tidal patterns, measure altitude, chart seafloors, identify ethnic communities, or bind nations, maps provide a potent lens through which people view the world and, in turn, spatially contextualize their experiences. Because of their power as historical sources, maps also serve as useful pedagogical devices when teaching about Japan. Recently, major research universities have pushed the importance of “original” undergraduate research. This is complicated if the student's interest is Tokugawa Japan, because archival documentation is notoriously difficult to read. Maps, however, offer an alternative. Of course, maps – particularly pre-modern maps drawn before the global spread of the cartographic sciences – contain marginal text; but because they are visual sources, they can, with the aid of an adept teacher, appeal to the creative inclinations of a notoriously visually oriented generation. Students learn that maps often represent – and often even drive – major historical events. This is certainly true of the maps drawn by Mamiya Rinzô, a collection of beautifully preserved pieces held at the Resource Collection for Northern Studies (Hoppô Shiryô Shitsu) at Hokkaido University.