| Tatsuoka Castle | |
|---|---|
龍岡城 | |
| Saku, Nagano, Japan | |
 Aerial photograph of Tatsuoka Castle site | |
  Tatsuoka Castle  Tatsuoka Castle | |
| Coordinates | 36°11′46″N 138°30′06″E / 36.19602°N 138.50167°E |
| Type | Star fort |
| Site information | |
| Open to the public | No |
| Condition | Ruins |
| Site history | |
| Built | 1867 |
| Built by | Matsudaira Norikata |
| In use | until 1868 |
| Garrison information | |
| Past commanders | Matsudaira Norikata |
Tatsuoka Castle (龍岡城, Tatsuoka-jō) was a Bakumatsu period pentagonal "star fort" located in what is now part of the city of Saku, Nagano prefecture. It was the primary fortress of Tatsuoka Domain, ruled by the Ogyū-Matsudaira clan. Along with the Goryōkaku in Hakodate, Hokkaidō, it is one of only two star fortresses in Japan, and has been the castle ruins have been designated as a National Historic Site since 1934.[1]