Maps can be highly informative and useful sources, whether as the primary subject of a paper or as supporting evidence for other research projects. Yale has an extensive collection of Japanese maps and maps of Japan by European visitors, spanning some four centuries. Most of Yale's maps are contained in the Map Department, although there are also compilations of maps in the SML stacks and in other Yale collections.
To search for maps, use an advanced search in Orbis. Select 'More Limits', and highlight 'Maps' and 'Globes' in the 'Medium' dialog box, as well as 'Archives and Manuscripts', 'Printed Maps', and 'Manuscript Maps' in the 'Item Type' box. After setting the limits, perform a keyword search; a search for 'Japan', for instance, returns 197 results.