Marugame Castle

Overview

Marugame Castle (丸亀城, Marugame-jō) is an Edo Period Japanese castle in the city of Marugame, Kagawa Prefecture, Japan. The castle stands in the centre of Marugame city, in former Sanuki Province on the island of Shikoku. Construction began in 1597, during the Azuchi–Momoyama period (1573–1603), in the second year of the Keichō era (慶長). The castle site has been protected as a National Historic Site since 1953.

During the Edo Period, Marugame Castle served as the seat of Marugame Domain, ruled by the tozama Kyōgoku clan under the Tokugawa Shogunate. The castle is counted among the 100 Fine Castles of Japan and is one of only a dozen Japanese castles to retain an original wooden tenshu built before 1860.

History

The castle’s origins date to 1597, when construction began under the direction of Ikoma Chikamasa, the daimyō of Sanuki Province. The initial fortification occupied the same hilltop site that the later castle would use, taking advantage of the natural elevation to command the surrounding plain and the Seto Inland Sea approaches.

In the early Edo Period, the Ikoma clan lost control of Sanuki, and the domain passed to the Kyōgoku clan. The Kyōgoku, a tozama (outside) house, were installed at Marugame and undertook major rebuilding of the castle during their tenure. The stone walls that survive today, including the famous fan-shaped base of the main keep, date largely from this period of expansion and reinforcement.

The castle remained the administrative centre of Marugame Domain throughout the Edo Period. The domain’s headquarters were located at the castle, and the Kyōgoku lords governed their territory from the tenshu and the surrounding honmaru (main bailey). With the Meiji Restoration in the late 19th century, the feudal domain system was abolished, and the castle lost its military and administrative function.

In 1953, the castle site was designated a National Historic Site, protecting the surviving earthworks, stone walls, and structures. The original tenshu, which had survived the end of the samurai era, continued to stand and is now one of the few pre-1860 wooden keeps remaining in Japan.

What Stands There Today

The most significant surviving structure is the original tenshu, a three-tiered, three-storey wooden keep. It is one of only twelve Japanese castles with an original wooden tenshu built before 1860, making it a rare example of Edo Period castle architecture that has not been reconstructed in concrete or steel.

The castle is surrounded by extensive stone walls, including the distinctive curved base beneath the tenshu. These walls are considered among the finest examples of Japanese castle masonry and are a major reason the site draws visitors. The castle grounds also include the 亀山公園こどもの国 (Kameyama Park Children’s Land), the 丸亀市城内グラウンド (Marugame Castle Grounds athletic field), and the Marugame City Museum, all located within the castle precinct.

The site hosts the Marugame Castle Festival, an annual event that brings the castle grounds to life with performances and stalls. The castle is also listed among the 100 Best Green Areas of Kagawa, reflecting the wooded hilltop setting within the city.

The Name in Japanese

The Japanese name is 丸亀城, read in kana as まるがめじょう, and in romaji as Marugame-jō.

Breaking the name down character by character:

• 丸 (まる, maru) — meaning “round” or “circle.” In castle names, this character often appears as a prefix, and here it forms the first element of the city and castle name.
• 亀 (かめ, kame) — meaning “turtle.” The turtle is a symbol of longevity in Japanese culture, and the character gives the castle its distinctive name. Together, 丸亀 (Marugame) means “round turtle,” a name that likely refers to the rounded hill on which the castle stands, which resembles a turtle’s shell.
• 城 (じょう, jō) — meaning “castle.” This is the standard suffix for Japanese castle names, read as jō when attached to a place name.

The full name, 丸亀城, thus reads as “Round Turtle Castle.” The kana reading まるがめじょう follows the standard on-reading of 城 as jō in compound castle names, while the first two characters are read with their kun-readings, まる and かめ.

Visiting and Context

Marugame Castle is located in the centre of Marugame city, in Kagawa Prefecture on the island of Shikoku. The castle sits at coordinates 34.2861910, 133.8001940, on a hill that rises directly from the surrounding urban area. The site is accessible on foot from Marugame Station, and the climb to the tenshu passes through the castle’s stone walls and gates.

Visitors can enter the original tenshu, which retains its wooden interior and steep staircases. The top floor offers views over the city and, on clear days, across the Seto Inland Sea. The surrounding Kameyama Park provides green space within the castle grounds, and the Marugame City Museum offers context on the castle’s history and the domain that governed from it.

The castle’s inclusion in the 100 Fine Castles of Japan places it on a national circuit of historically significant fortifications. For students of Japanese, the name offers a compact lesson in kanji composition: a common noun prefix, an animal character with cultural resonance, and the universal castle suffix. The survival of the wooden tenshu makes Marugame a rare place to see an Edo Period keep exactly as it was built, without later reconstruction.