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Updated:March 22, 2021

Komoro Castle Ruins Kaikoen Park Postcard

日本語

簡体中文

Komoro Castle Ruins Kaikoen Park

Komoro Castle Ruins Kaikoen Park

About the park

  Komoro Castle Ruins Kaikoen Park is listed in the Best 100 Castles in Japan, the Best 100 Sites for Cherry Blossom Viewing, and the Best 100 Historical Parks in Japan. The castle is a fort built on the natural terrain, and is called a Sunken castle because the whole castle structure is constructed under the town around it. This is a unique castle structure believed to be only one in Japan. Usually castles are built on a high place because attacking enemies from a high place is more effective.

  The origin of Komoro Castle is dated back to over 800 years ago, at the time of battles between the Minamoto and Taira clans. It is believed that Yamamoto Kansuke, a strategist of a famous feudal lord Takeda Shingen during the Warring State Period surveyed and designed the castle. From the Azuchi Momoyama era to Edo era, Sengoku Hidehisa, portrayed in manga as the protagonist, was the chatelaine. He fixed the Otemon Gate and stone foundations that still exist even now. During the Battle of Sekigahara in 1600, the main force of the Eastern Army entered the Komoro Castle, from where they attacked Ueda Castle of Sanada Masayuki, who belonged to the Western Army.

  Now the castle has been developed into a park. The visitors can feel nostalgia while enjoying cherry blossoms the in the spring, colors in the fall, and other flora in four seasons in the backdrop of the moss-covered stone foundations.

  The photo was taken at San-no-mon (the third gate, Nationally-Designated Important Cultural Property). In Nagano, cherry blossoms bloom later than other areas, and you can enjoy full bloom until late April. Please enjoy slowly approaching season in Nagano after cherry blossoms have fallen in the Tokyo area.

  For more details about and access to Komoro Castle Kaikoen Park, please see the website of Komoro Tourism Bureau( The external site opens in a separate window ). ※The linked web pages are currently in Japanese only.

Other Castles and Points of Interest Nearby

  In addition to Mt. Asama, following mountains are listed in the Best 100 Mountains in Japan in the Saku Region.


Komoro Castle Otemon Gate( The external site opens in a separate window )

※The linked web pages will be automatically translated into English by Google Translate.


Shakusonji Temple (Nunobiki Kannon)( The external site opens in a separate window )

※The linked web pages will be automatically translated into English by Google Translate.


Tatsuoka Castle Star Fort( The external site opens in a separate window )

※The linked web pages will be automatically translated into English by Google Translate.

  For more points of interest, please visit Komoro Tourism Bureau( The external site opens in a separate window ). ※The linked web pages are currently in Japanese only.

  For flower viewing in the Saku region, please visit Karuizawa Navigation( The external site opens in a separate window ). ※The linked web pages will be automatically translated into English by Google Translate.

A Gift for You, from Saku and Karuizawa

 Saku Regional Development Bureau created postcards for tourists in Karuizawa so that they will discover more about the Saku Region. There are 10 postcards, and they will be available free of charge at facilities in Karuizawa Town.

  For information, please visit the “A Gift for You, from Saku and Karuizawa” page.

※Click an image to view details of the photo.

Shiraito Falls

Mt. Asama

 Nakasendo Way (Motai Post Town)

 Koumi Line (Nobeyama ~ Shinano Kawakami)

Komoro Castle Ruins Kaikoen Park 

Saku Balloon Festival

Lake Shirakoma

The sky full of stars in Nobeyama

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佐久地域振興局商工観光課

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