The Koka Ninja House in Koka City, Shiga Prefecture, is a mansion-style facility with information and experiences related to the ninja of old. The building itself was built during the Edo period and used as the residence of Mochizuki Izumonokami, who held chief status in the the 53 Families of Koka, the group at the center of the Koka ninjutsu techniques, and it has been preserved in its original form.
Inside the building, visitors can see a variety of trick mechanisms created by the knowledge of the ninja, including hidden rooms used to escape from enemies, doors that swing around used for hiding, and pitfalls up to three meters deep. Shuriken that the Koka ninja actually used as well as written documents and scrolls are also on display, allowing visitors to deepen their understanding about the Koka ninja.

Photographs provided by the Biwako Visitors Bureau.