Tanaka Castle

Tanaka Castle is a historic flatland-style Japanese castle located in Fujieda, Shizuoka Prefecture, Japan. Originally constructed in 1537 by the Imagawa clan as a small stronghold to protect western approaches to Sunpu Castle, the site was significantly expanded in 1570 under Takeda Shingen to guard against Tokugawa forces. The castle's unique architectural layout, established during Takeda rule, features three concentric circular moats with four gates each, utilizing a distinctive maru umadashi style surrounded by crescent-shaped water defenses. Situated on a hill within the marshy Shida Plain between the Seto and Rokken rivers, its strategic position on the vital Tōkaidō highway connecting Edo and Kyoto made it a crucial military asset throughout the feudal era.

Following the rise of the Tokugawa shogunate, the castle served as the headquarters for Tanaka Domain and changed hands among various fudai daimyō before becoming the seat of a Honda clan branch in 1730. It holds notable historical significance as an occasional base for shogunal falconry expeditions and is famously alleged to be the location where Tokugawa Ieyasu consumed tempura shortly before his death. Although the main structures were demolished in 1872 after the Meiji Restoration and the grounds were largely converted into schools, houses, and rice fields, the site retains significant archaeological value.

Today, Tanaka Castle is partially reconstructed and open to the public. While most original buildings are gone, visitors can still observe remnants of the extensive moat system and stonework that define its circular design. A large yagura turret, relocated and reconstructed in 1992, now stands on the grounds serving as a local history museum. This preservation effort allows the site to function as both a cultural landmark and an educational resource, commemorating its complex history from the Sengoku period through the Edo era.