Do you know Japan’s Kanto region?
Kanto lies in eastern Honshu and consists of seven prefecture-level areas: Ibaraki, Tochigi, Gunma, Saitama, Chiba, Tokyo, and Kanagawa.
Its roads spread out from Tokyo, Japan’s capital, through a vast urban area and continue toward the coast and the mountains.
What kinds of roads cross this region, and how many vehicles use them each day?
This article uses Japan’s Ministry of Land, Infrastructure, Transport and Tourism Road Traffic Census to present the Kanto region’s road traffic volumes through a map and data.
Compare them with road conditions in your own country. What differences can we discover together?
Kanto Region Road Traffic Volume Map
First, let us explore the Kanto region’s roads on the map.
You can switch between expressway-category roads (expressways and urban expressways in this dataset), general national roads, prefectural roads, and surveyed city roads.
Select a circle to see the road name and traffic volume for that survey section. Switch between 2015 and 2021 to compare the same section across the two years.
This map does not show every road in the Kanto region. It shows survey sections for which traffic volumes were published in the Ministry of Land, Infrastructure, Transport and Tourism Road Traffic Census.
How to use the map
- Use the road-category buttons to switch between expressway-category roads, general national roads, prefectural roads, and surveyed city roads.
- Zoom in to see individual circles representing traffic volumes.
- Compare traffic volumes by the size and color of the circles.
- Select a circle to see the weekday 24-hour traffic volume for that location in 2015 and 2021.
- The official basic road section to which the selected traffic volume applies is shown as a fluorescent green line with a dark outline. It does not represent the entire route.
- Search by route name, prefecture name, or survey-section name.
Sections shown on the map
The map shows 17,559 basic road sections across Kanto’s seven prefecture-level areas whose representative locations and section lines could be verified using the ministry’s official web map.
These consist of 691 expressway-category sections, 4,467 general national road sections, 12,012 prefectural road sections, and 389 surveyed city road sections.
This is not a map of every local road. The city-road category includes only some major roads recorded in the national survey. Traffic surveys conducted independently by local governments have not been added.
Comparison with 2015
Of the 17,559 basic road sections shown on the map, 16,690 can be compared between 2015 and 2021.
Where no corresponding 2015 traffic volume was found in the official materials, only the 2021 figure is shown.
New roads and changes to section boundaries can make direct comparison between the two years impossible. Historical figures that could not be verified have not been estimated or filled in.
How Did Traffic on Kanto’s Expressway-Category Roads Change?
Let us compare traffic on the Kanto region’s expressway-category roads in 2015 and 2021.
Across the 665 basic road sections that can be compared in both years, the combined traffic volume decreased by 8.2%.
This total is not the number of individual vehicles driven in the Kanto region. If the same vehicle passes through several survey sections, it is counted once in each section.
Move the Map from Tokyo Across All Seven Areas
Circles indicating traffic volume are densely concentrated around Tokyo.
Move the map from there and roads extend in many directions into Saitama, Chiba, Kanagawa, Ibaraki, Tochigi, and Gunma.
Even in central Tokyo, some sections are shown with smaller circles than the surrounding roads.
How does the pattern of circles change when you switch between expressway-category roads, general national roads, prefectural roads, and surveyed city roads?
Follow Kanto’s Roads for the First Time
You do not need to know the Kanto region’s place names or road names in detail.
To me, the roads stretching out in many directions from around Tokyo look like an octopus moving with its arms spread wide. What shape do you see?
Start by searching for a place you know, a place you have heard of, or somewhere you plan to visit for travel or business.
Select a circle nearby, check the road name and traffic volume, and then move the map to other parts of the region.
The map and data may help you discover a road in Kanto that you have never encountered before.
Sources and Notes
- Source: Ministry of Land, Infrastructure, Transport and Tourism, 2021 Road Traffic Census: General Traffic Volume Survey (令和3年度 全国道路・街路交通情勢調査 一般交通量調査)
- Comparison source: Ministry of Land, Infrastructure, Transport and Tourism, 2015 Road Traffic Census: General Traffic Volume Survey (平成27年度 全国道路・街路交通情勢調査 一般交通量調査)
- Traffic volume is generally the combined weekday 24-hour motor-vehicle traffic volume in both directions.
- Combined values are extended totals calculated by adding the traffic volume of each basic road section. They are not counts of unique vehicles actually driven.
- Only sections whose locations could be verified in official materials are shown on the map.
- Results from the 2025 survey will be added after their official publication. They are not used at present.