The Koka Ninja House (甲賀流忍術屋敷), located in Koka City, Shiga Prefecture, is one of the only remaining residence of real ninja open to the public in Japan. Originally built during the Edo period as the home of the Mochizuki family, one of the legendary 53 Koka ninja families, this authentic ninja house offers visitors a rare glimpse into the elusive lifestyle of Japan’s famed shadow warriors.

Complete with hidden passages, trap doors, and escape routes, the house doubles as both a museum and a living historical site. Beyond its clever architecture, the house showcases ninja tools, weapons, and original documents that reveal the truth behind centuries of myth and mystery.

A Brief History of the Koka Ninja House

  • Built: Genroku era of the Edo period (1688–1704)
  • Original Residents: The Mochizuki family, one of the most influential Koka ninja clans
  • Significance: The last remaining publicly accessible house used by real ninjas
  • Location: Koka countryside, Shiga Prefecture

The Koka Ninja House, is an authentic ninja house built during the Edo era. It was the residence of the Mochizuki family, one of the leading ninja families of the Koka ninja clan. 

Designed with sophisticated traps and layouts to evade or ambush enemies, the residence embodies the true essence of ninja tactics: invisibility, subversion, and survival. Today, it remains a valuable heritage site, teaching visitors about Japan's warrior-spies through direct experience.

Recommended Tour: Snow Monkey Resort's 1-Day Tour from Nagoya: Myths and Mystery of Ninja and the Tokaido Road not only gives insight into the daily lives of ninja but also takes you along the most important route of Edo-era Japan, the Tokaido road, as you are led by an experienced English-speaking guide on a full-day tour from Nagoya.

The Mochizuki Clan: Leaders of the Koka Ninja

The Mochizuki family were once powerful landholders with 16 pastures in the region. Their surname—“Mochizuki” (望月)—originates from a Heian-period ritual held on the night of the full moon. Their family crest, Kuyoumon, displays a central moon surrounded by eight stars, symbolizing the clan’s alignment with the lunar cycle (and stealth).

The Mochizuki family led the 53 ninja families of Koka, forming a self-governed coalition that often acted independently of central authorities. While labeled as “ninja,” these warriors were also farmers, pharmacists, and merchants—everyday citizens who transformed into elite operatives when duty called.

Iga vs. Koka: Rivals or Allies?

Modern media often portrays Iga and Koka ninjas as fierce rivals. In truth, history tells a more complex story:

  • Both schools were among the most prominent in feudal Japan
  • They often collaborated, such as in support of the Rokkaku clan
  • Ties through intermarriage and mutual defense blurred rivalries
  • Occasionally, disputes did arise, especially as clans jockeyed for influence

The two regions formed the united cultural zone known as “Koi Ikoku”, and together they shaped much of what is now recognized as ninjutsu tradition.

Frequently Asked Questions (FAQ)

Is the Koka Ninja House authentic?

Yes. It was the actual residence of the Mochizuki family and includes original features used by real ninjas in the Edo period.

Can I experience the traps and hidden passages myself?

Yes! Visitors can explore rotating walls, hidden staircases, and other ninja tricks firsthand.

Is it suitable for kids or families?

Absolutely. Children especially enjoy the interactive elements and ninja tools on display.

Are there English tours of the Koka Ninja House?

We at Snow Monkey Resorts are proud to offer a guided tour in English of the Koka Ninja House and several other ninja-related locations around the region.

How do I get to the Koka Ninja House?

From Nagoya Station, take the Kansai (JR Central) Line to Kameyama Station, then transfer to the Kanasi (JR West) Line bound for Tsuge Station. At Tsuge Station, transfer to the Kusatsu Line to Konan Station. The Koka Ninja House is a 25 minute walk from Konan Station. Total travel time: ~2.5 hrs / 1690JPY

For ease of transportation and the added benefit of an English-speaking guide, we highly recommend joining a guided tour.

Recommended Tour: Snow Monkey Resort's 1-Day Tour from Nagoya: Myths and Mystery of Ninja and the Tokaido Road not only gives insight into the daily lives of ninja but also takes you along the most important route of Edo-era Japan, the Tokaido road, as you are led by an experienced English-speaking guide on a full-day tour from Nagoya.

Of course, we also offer private tours and transport in and around the Nagoya area, and other regional destinations. We can also arrange for both custom tours with an English-speaking guide or a private charter. 

Our drivers and vehicles are fully certified, allowing us to transport you to and from your preferred destinations in combination with any activity that suits your schedule. All vehicles are well-maintained and in good condition, allowing you to relax and enjoy your ride to wherever you are going. 
With door-to-door service, we can pick you up from where you are and take you to where you want to go anywhere in Central Japan and the neighboring regions.

For more information, please check our standard charter rates or contact us for a custom trip. We’d love to be part of your adventure in Central Japan and help you discover even more!

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