Dai Nihon Saiken Dōchū Zukan was made by Tomonari, Shōkyoku in 1850. It is a large map (34cm by 141.5cm) detailing information about Honshū, Kyūshū, and Shikoku.
In order to organize the massive amount of information that it conveys, icons are used to indicate the following:
Cities – Red circles (the larger the city, the smaller the circle)
Yellow squares – Castles
Hexagons – Province name
White cartouches – Places where one can stay
Red rectangles – Pilgrimage sites (numbered)
Red lines – Major highways
Dotted lines – Sea routes
Black lines with black triangle – Provincial borders
The key to these icons can be found in the lower right corner of the map.
On the far left of the map there is a detailed table which records distances between sites and various highway tolls. The tolls are separated into either two or three categories. Two of these categories seem to be the toll for someone on foot and the toll for one on horseback. In some places there is a third category listed, but it has thus far proven to be illegible.
An interesting part of this map is that in order to reconcile the actual shape of Japan with the straightened version depicted here (I would theorize that this was done in order to conserve space), the map maker has included three compasses on the map. The first can be found north of the island of Kyūshū. At this point on the map, the orientation is still relatively accurate, and so the compass indicates North to be towards the top of the page. As one moves towards the right along the map, they find another compass on the Pacific side of Honshū. To account for the now skewed orientation in that area, the compass has been rotated to give a more accurate indication of which way is north. The third compass can be found on the other side of Honshū, in the Sea of Japan. The rotation of the compass here is more extreme than in the second compass, as the perspective here is quite inaccurate.
Where the intended use of this map is concerned, I am inclined to state that it was, in fact, made to be used by travelers on the road as opposed to a more decorative purpose. My reasoning is supported by three characteristics of the map. First, the rotation of the three compasses seem to indicate an effort at maintaining topographical accuracy. This would naturally be important to someone attempting to travel using the map’s information. Second, the large amounts of practical information would be unnecessary for a decorative map. This, however, could still be useful if the map was made to be displayed instead of carried. Except that my third reason is the small fact that the title section of the map is only half the length of the whole work. I do not feel that it is too large a jump to say that this would indicate that the map was made to be folded into the size of that small title section, and thus made into something which a traveler could easily carry with them on the road.
“Dai Nihon saiken dōchū zukan.” University of British Columbia – Rare Books and Special Collections: Japanese Maps of the Tokugawa Era. April 9th, 2017. https://open.library.ubc.ca/collections/tokugawa/items/1.0216353#share