Takamatsu Castle (Tamamo Park)

Takamatsu Castle, also known as Tamamo Castle, represents one of only three Japanese castles built directly on the seacoast, where its moats filled with seawater rather than fresh water, creating a unique defensive system. Though the main keep no longer stands, the castle ruins preserve impressive stone walls, restored gates, and corner turrets that demonstrate the sophisticated military architecture of the Edo period. The castle grounds have been transformed into Tamamo Park, a peaceful urban green space where historic structures blend with gardens and open lawns. The most distinctive feature is the seawater moat system, where tidal flows from the nearby Seto Inland Sea ensured the moats always remained filled, while preventing enemies from crossing by swimming. The moats still host marine life including sea bream, mullet, and occasionally small sharks that enter during high tide, creating an unusual aquarium-like environment within a castle defense system. Several original gates survive, including the impressive Ote-mon main gate with its traditional two-story yagura tower, while the Tsukimi Yagura moon-viewing turret offers excellent views across the moats to the modern city beyond. The park's northern area preserves the Hiunkaku villa, a beautiful Japanese residence with traditional architecture and garden.