A core city (中核市, Chūkakushi^?) is a class of Japanese city created by the first clause of Article 252, Section 22 of the Local Autonomy Law of Japan. Core cities are delegated many functions normally carried out by prefectural governments, but not as many as designated cities. To become a candidate for core city status, a city must satisfy the following condition:

Application for designation is made by a city with the approval of both the city and prefectural assemblies.

As of 2009, 41 cities have been designated core cities:

The following cities have populations greater than 300,000 but have not yet been nominated. (Cities planning to apply for core city status are not shown. ※Special Cities)

Core may refer to:

A city is a relatively large and permanent settlement. Although there is no agreement on how a city is distinguished from a town within general English language meanings, many cities have a particular administrative, legal, or historical status based on local law.

For example, in the U.S. state of Massachusetts an article of incorporation approved by the local state legislature distinguishes a city government from a town. In the United Kingdom and parts of the Commonwealth of Nations, a city is traditionally a settlement with a royal charter. Historically, in Europe, a city was understood to be an urban settlement with a cathedral.

Cities generally have complex systems for sanitation, utilities, land usage, housing, and transportation. The concentration of development greatly facilitates interaction between people and businesses, benefiting both parties in the process. A big city or metropolis usually has associated suburbs and exurbs. Such cities are usually associated with metropolitan areas and urban areas, creating numerous business commuters traveling to urban centers for employment. Once a city expands far enough to reach another city, this region can be deemed a conurbation or megalopolis.