Kijō Park (亀城公園): On the Grounds of Tsuchiura Castle (土浦城)

The East Turret of Tsuchiura Castle

Kijo Park (亀城公園), located northwest of Tsuchiura Station in Ibaraki Prefecture, sits on the former site of the honmaru (main enclosure) and ninomaru (second enclosure) of Tsuchiura Castle (土浦城), originally founded during the Muromachi period in the Eikyo era (1429–1440). The castle was also known as Kijo (亀城), meaning "Turtle Castle," for its moats, which gave it the appearance of a turtle floating on water.

Monument marking the site of the honmaru (front) and the East Turret (back)

Yagura Gate

During the Edo period (1603–1868), the castle was governed by the Matsudaira, Nishio, Kutsuki, and Tsuchiya clans.

Following the Haijo Edict (Castle Abolishment Law) of 1873, the site was repurposed several times — as the Tsuchiura Prefectural Office, the Niihari Prefectural Office, the Tsuchiura Branch Office of Ibaraki Prefecture, and later, the Niihari County Office.

In 1898, plans to convert the area into a public park emerged when the Tsuchiya family and Ibaraki Prefecture — the landowner and administrator — donated the site to Tsuchiura. Construction began in 1934, and the park officially opened in 1935.

Maekawaguchi Gate

Kasumi Gate

Several Edo-period structures remain in the park, including the Yagura Gate (櫓門), Kasumi Gate (霞門), and the relocated Maekawaguchi Gate (前川口門). The Maekawaguchi Gate, originally built in the late Edo period in the Koraimon (高麗門) style — a type of Japanese castle gate with a gabled roof supported by pillars with two side structures each also bearing a gabled roof — is said to have once stood between the Takekuruwa (samurai residence) and the townhouse area. In 1885, it was moved to serve as the gate for the Tsuchiura kocho (village head) office hall, later the town hall. In 1920, it was relocated again to Sokaku-ji, a Buddhist temple in Tsuchiura’s Otemachi district, where it became the temple's sanmon (main gate). In 1981, it was transferred to its current location — where the ninomaru entrance gate of Tsuchiura Castle once stood — following a donation from the temple.

West Turret

Shotoku Taishi-do

Tsuchiya Jinja

The East Turret (東櫓), believed to have been constructed during the Nishio clan's rule, was destroyed in the Meiji period and reconstructed in 1998. It now functions as an exhibition hall. The West Turret (西櫓), damaged by Typhoon Kitty in 1949, was dismantled and later rebuilt in 1991.

Kijo Park is also home to two Shinto shrines: Shotoku Taishi-do (聖徳太子堂) and Tsuchiya Jinja (土屋神社).

References:

• Tsuchiura City. (2020, June 2). 土浦発 未来への伝承 162 亀城公園のあゆみ. 広報つちうら. https://www.city.tsuchiura.lg.jp/data/doc/1590985756_doc_159_1.pdf
• Tsuchiura City. (2025, March 19). 名所・史跡の紹介. 土浦市 Tsuchiura City. https://www.city.tsuchiura.lg.jp/kanko-bunka-sports/kanko-matsuri-event/kanko/page001098.html