The town of Karuizawa, a representative resort in Japan, is not only a tourist destination with 8 million annual visitors, but also stands out as one of the premier summer houses areas in Japan. Using Karuizawa as a case study, the objectives of this study were (1) to clarify the location of summer houses and tourist recreation facilities at different times of the year using maps showing the areas, and (2) to summarise the spatial changes in Karuizawa after discussing the information value of maps showing them. The research methods used were a literature survey and a field survey, mainly based on maps. While in the Meiji period the center of construction of summer houses was on the area close to the Karuizawa-juku, post town, before and during the Showa period, the area expanded to other areas not facing the Karuizawa main road, and changed to a wider areas. Tourist and recreation facilities were located within or adjacent to the summer houses area south of the Karuizawa-juku, post town in the Meiji period, but disappeared with the expansion of the summer houses area and the construction of new areas.