was a

district A district is a type of administrative division that, in some countries, is managed by the local government. Across the world, areas known as "districts" vary greatly in size, spanning regions or counties, several municipalities, subdivisions o ...

located in

Tochigi Prefecture is a Prefectures of Japan, prefecture of Japan located in the Kantō region of Honshu. Tochigi Prefecture has a population of 1,943,886 (1 June 2019) and has a geographic area of 6,408 Square kilometre, km2 (2,474 Square mile, sq mi). Tochigi ...

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

. As of 2003, the district had an estimated

population Population typically refers to the number of people in a single area, whether it be a city or town, region, country, continent, or the world. Governments typically quantify the size of the resident population within their jurisdiction using a ...

of 40,915 and a

density Density (volumetric mass density or specific mass) is the substance's mass per unit of volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' can also be used. Mathematical ...

of 150.59 persons per km². The total area was 271.70 km².

Towns and villages

* Kuzu * Tanuma

Merger

* On February 28, 2005 - the towns of Kuzu and Tanuma were merged into the expanded city of Sano. Therefore, Aso District was dissolved as a result of this merger. Former districts of Tochigi Prefecture {{Tochigi-geo-stub