Imagine an ancient citadel whose moats are filled not with fresh water, but with salt water directly from the ocean. The remains of the Takamatsu Castle donjon foundation are a key part of the unique "sea castle" (Tamamo Castle), located in picturesque Takamatsu. Today, these are not just ruins, but a majestic monument to late 16th-century engineering, recognized as a national historic site that Japan is proud of.

The main feature of this site is the massive stone base (tenshudai), upon which the castle's main tower once stood. Located within Tamamo Park, the foundation serves as a wonderful observation deck, offering guests panoramic views of the sea and city blocks. The architectural ensemble is complemented by preserved watchtowers and ancient walls, creating an atmosphere of the former greatness of the samurai era.
Beyond its historical value, the site attracts tourists with its unusual ecosystem: because the moats are connected to the Seto Inland Sea, you can see sea fish swimming right at the foot of the fortress walls. This place is rightfully included in the list of Japan's Top 100 Castles and is a must-visit for all lovers of Eastern history and aesthetics.