In Japanese addresses, “Ken” (Prefecture), “Gun” (District), “Shi” (City), “Mura” (Village), “Ku” (Ward), “Machi” or “Cho” (Town), “Aza” (Subdivision), “Chome” (Block), “Banchi” (House Number), and “Go” (Unit Number) represent hierarchical units to specify administrative divisions and address locations. Below are the definitions and roles of each unit:
1. Ken (Prefecture)
Definition: The fundamental administrative unit in Japan, dividing the nation into 47 prefectures.
Examples: Hokkaido, Tokyo-to, Osaka Prefecture, Fukuoka Prefecture
Role: Serves as a local government body conducting regional administration delegated by the national government, covering areas such as education, police, and public works.
Characteristics: Includes “To” (Tokyo-to), “Do” (Hokkaido), and “Fu” (Osaka-fu and Kyoto-fu), all equivalent to prefectures in administrative hierarchy.
2. Gun（District）
Definition: A subdivision of a prefecture, typically comprising multiple towns and villages. Although its administrative role has largely disappeared, it remains in use for address and place names.
Examples: Kasuya District (Kasuya-gun), Fukuoka Prefecture
Role: Historically functioned as a basic unit of regional administration until the Meiji Era. Currently, it is used only in address formatting.
Characteristics: Used for towns and villages but not for cities.
3. Shi (City)
Definition: A large-scale municipality under a prefecture with its own administrative authority.
Examples: Fukuoka City, Nagoya City, Yokohama City.
Role: Acts as a local government providing public services and regional development.
Characteristics: Promoted from towns or villages upon meeting criteria for population, area, and tax revenue. Cities are not part of districts.
4. Ku (Ward)
Definition:
- An administrative division of designated cities (e.g., Yokohama, Osaka).
- In the case of Tokyo’s special wards (e.g., Shinjuku Ward, Setagaya Ward), the ward itself functions as a local government.
Examples: Shinjuku Ward, Tokyo; Kita Ward, Osaka.
Role: Established to improve administrative efficiency and resident services.
Characteristics: Wards in designated cities are part of the city, while Tokyo’s special wards have their own local government authority.
5. Machi / Cho（Town）
Definition:
- A municipality under a district (e.g., Karuizawa Town, Nagano Prefecture).
- Also refers to smaller sections (neighborhoods) within cities or wards.
Examples: Jinbocho, Chiyoda Ward, Tokyo
Role: Can serve as a local government or as a unit in address formatting.
Characteristics: Differentiation is necessary between towns as municipalities and towns as address units.
6. Mura (Village)
Definition: A small municipality belonging to a district, like towns.
Examples: Kitadaito Village, Okinawa Prefecture; Minamimaki Village, Nagano Prefecture.
Role: Provides public services as a local government.
Characteristics: Found in areas with small populations and economic scale. Villages may be promoted to towns or cities as their population increases.
7. Aza (Subdivision)
Definition: A smaller unit within a town or village, often used in place names.
Examples: ○○ Village, Aza △△.
Role: Used in land registries and address formatting to indicate specific areas or plots.
Characteristics: Includes “Oaza” (larger subdivision) and “Koaza” (smaller subdivision).
8. Chome (Block)
Definition: A further subdivision within a city, ward, or town.
Examples: 3-Chome, Yakuin, Chuo Ward, Fukuoka City.
Role: Divides neighborhoods for postal delivery and address identification.
Characteristics: Helps pinpoint general locations within a town.
9. Banchi (House Number)
Definition: A number indicating a specific parcel within a block.
Examples: 3-16 Yakuin
Role: Identifies individual plots of land or buildings in an address.
Characteristics: Originally derived from land registry numbers, it is now part of modern address systems.
10. Go (Unit Number)
Definition: A number further dividing house numbers, used to specify buildings or rooms.
Examples: 3-16-26 Yakuin
Role: Specifies individual buildings or rooms within a house number.
Characteristics: Enables precise identification of units within a plot.
Summary
Japanese addresses are organized hierarchically, from large administrative units (Prefecture, City, District) to smaller subdivisions (Town, Subdivision, Block, House Number, Unit Number).