Kariwa District, Niigata
As of July 1, 2019, the district has an estimated population of 4,578 and a density of 174 persons per km. The total area is 26.27 km. The district (excluding the west side of Kashiwazaki) was once part of the now-defunct Koshi District until the Heian period when the district was created under the name of Mishima District. Prior to the split, Mishima District covers the cities of Kashiwazaki (excluding the western part of the city), village of Kariwa, Nagaoka (parts of the former towns of Oguni and Koshiji). When Santō District splits off from Koshi  District during the Edo period, Mishima was renamed to Kariwa. In 1940, the town of Kashiwazaki became a city. After Kashiwazaki merged the surrounding areas, the district continued on to shrink. On April 1, 2005, the town of Oguni merged into the city of Nagaoka and a month later, the towns of Nishiyama and Takayanagi merged into the city of Kashiwazaki. With this merger, Kariwa District has only the village of Kariwa left.