Nihonmatsu Castle is located in Kakunai, Nihonmatsu, Fukushima Prefecture, and is counted as one of Japan's 100 best castles.

Construction of the castle was begun in the 21st year of the Ouei era (1414) by Mitsuyasu Hatayama (Nihonmatsu). Upon entering the Warring States period, the Nihonmatsu clan fought bitterly with Masamune Date. Masamune was outraged when the Nihonmatsu clan kidnapped his father after pretending to surrender. In revenge, Masamune annihilated the Nihonmatsu clan in the 4th year of the Tensho era. Since then, the rulers of Nihonmatsu Castle have changed numerous times over many generations.

Mitsushige Niwa greatly refurbished the castle in the 20th year of the Kannei era (1643), and resided there until the Meiji Restoration. During the Boshin Wars, Nihonmatsu Castle sided with the government, but was overrun in the 5th year of the Meiji period (1872) and eventually abandoned.

The castle grounds are currently the site of Kasumi-ga-jou Park, and the stone walls and structures remain. A Kansekimeihi monument stands at the entrance. The Nihonmatsu Castle was designated as a National Monument in 1935.