Highway Data Discussion > In-progress Highway Systems & Work
Japan: National Highways 一般国道 system
nezinscot:
All of my driving in Japan has been on the national highway system and on prefectural roads, not the expressways. I wanted to add this mileage but did not find a highway system for the "common" national highways.
Is anyone working on a highway system for the 55000+ km of national highways? If no one is and you all feel the system is needed, I would be willing to help with the task.
I speak, read, and write intermediate level Japanese and would be willing to use this painfully acquired skill to dig through the ministry websites and GIS systems for original sources. I am also familiar with the problems related to Japanese street naming and addresses. The file creation and manipulation part of the task shouldn't be a problem because I spent years working in science and engineering-related IT.
The work would also help me improve my Japanese. I was definitely never taught highway-related vocabulary in class...
michih:
Great news :) si404 developed the existing systems. I think he will answer what he thinks about it.
General note:
The requirements for developing new systems are described here: https://travelmapping.net/participate.php?u=michih&#hwydatamanager
When you reach stage 5 (I guess you are currently at stage 3?), jpntk and jpne could be your candidates for the peer-review:
https://forum.travelmapping.net/index.php?topic=3004
https://forum.travelmapping.net/index.php?topic=3668
I started the jpne system peer-review last May but gave up quite soon and will not work on it again any time soon.
nezinscot:
I'm at level 4. I read the developer manual before I volunteered so that I could have an idea of what the work might entail. I no doubt need to give it another close reading.
Japanese numbered highways have some interesting quirks --- most intersecting roads are nameless, roads can span multiple islands, mountain roads can use widely divergent paths for each direction, roads may have two options (one a new tunnel the other the old twisty mountain road), ridge roads often wind back and forth across prefectural borders, etc. At least the GSV coverage is good.
There are 47 prefectures, so a complete Japanese system would be a mini-US. And if we include the extensive train and metro systems, the task gets even bigger.
nezinscot:
I have almost completed my review of the Japanese expressway systems and would like to work on the Japanese national highway system next.
There are 400+ national highways in Japan, plus hundreds of related bypasses and older routes that are still considered part of the national highways. In all there could be ~1000 separate entries in this new system. I believe we are trying to create smaller systems, so if I started this work, I would like to create separate systems for each prefecture (province). There are 47 prefectures.
Separate systems for each prefecture will also help deal with the abundant duplicate prefectural road names found on the longer national highways. For example N4, the longest national highway, intersects P8 and P25 in four separate prefectures.
There is information online about the newer parts of the national highway system, especially the bypasses around towns. GSV coverage is very good in urban areas and adequate in rural areas. Highways are usually well marked with route and mileage markers. Plus there are enthusiast websites in Japanese that cover the routes in detail, for example http://hgf03030.a.la9.jp/index.htm.
I would like to know if you all consider this a project worth doing.
michih:
--- Quote from: nezinscot on September 13, 2021, 12:30:19 pm ---I believe we are trying to create smaller systems, so if I started this work, I would like to create separate systems for each prefecture (province). There are 47 prefectures.
Separate systems for each prefecture will also help deal with the abundant duplicate prefectural road names found on the longer national highways.
--- End quote ---
I think that we can go with smaller systems through the development process as we did for gbna or deub but the systems should be merged on activation. However, we should not do it by prefectures since the routes (wpt files) would need to be changed. This would affect users.
--- Quote from: nezinscot on September 13, 2021, 12:30:19 pm ---For example N4, the longest national highway, intersects P8 and P25 in four separate prefectures.
--- End quote ---
There is a simple solution: https://travelmapping.net/devel/manual/wayptlabels.php#over2
--- Quote from: nezinscot on September 13, 2021, 12:30:19 pm ---I would like to know if you all consider this a project worth doing.
--- End quote ---
I think so! We have 7 users with travels in Japan so far. We have regions or systems with less travelers.
Navigation
[0] Message Index
[#] Next page
Go to full version