Japan is an archipelago consisting of four main islands: Honshu, Hokkaido, Kyushu, and Shikoku. The majority of the population is concentrated in coastal areas and plains due to the mountainous and rugged terrain making up much of the interior. The cities of Tokyo, Osaka, and Nagoya are some of the most densely populated urban areas in the country. Ancient settlements were often located near rivers for access to water and fertile land for agriculture.
