Toyotomi Hideyoshi used a massive 3-kilometer dam to submerge the castle in just 12 days.
The castle is nicknamed 'The Water Castle' because the entire base was submerged during the 1582 siege.
Black ink stones were found in the area, indicating the site's proximity to historic regional trade routes.
The site contains the Shimizu Muneharu seppuku monument, honoring the commander who surrendered his life to save his soldiers.
Bichu Takamatsu Castle is historically significant as the site of the 1582 Siege of Takamatsu, where Toyotomi Hideyoshi successfully defeated the Mori clan by diverting the Ashimori River to flood the fortress. The castle, known as Mizujiro or 'Water Castle,' is one of Japan's three major water-based fortresses. Today, the site functions as a public park featuring earthen ramparts, a central pond, and commemorative monuments rather than reconstructed stone buildings. Visitors can explore the remnants of the main bailey and the elevated embankment that served as a dam during the historic flood. The park is surrounded by lotus fields that bloom seasonally, referencing the tragic drowning of the castle's defenses. It serves as an open-air historical site illustrating civil engineering tactics used in Sengoku-period warfare.
From the elevated embankments looking over the lotus fields toward the central monument.
Bring insect repellent during the summer months due to the marshy, park-like terrain.
Wear comfortable walking shoes suitable for gravel paths and earthen embankments.
Read the site's historical placards, which provide maps of the original flood trajectory.
Do not attempt to walk on restricted earthwork sections marked for preservation.
