The 1st Kaga domain head, Maeda Toshiie, adopted the Chudo spirit of the Nichiren Buddhist sect and Hogekyo as his political philosophy and built Myoryuji Temple as a place to pray for the domain's peace. This was in the 13th year of the Tensei period (1583). Later, in the 20th year of the Kanei period (1643), the 3rd domain head, Maeda Toshitsune moved the temple to its present place.

At the time of Toshitsune, the Tokugawa government had established its base and sent spies to various domains. Toshitsune let his nose hair grow and pretended to be stupid in order to deceive the spies. But Toshitsune is also famous for developing industry and the performing arts, and built temples as emergency barracks. Myoryuji Temple is the main temple among these.

It might look two-storied from the outside but in fact it is four-storied with seven layers. There are many contraptions everywhere in the temple such as a hidden walkway, room, stairs and changeable fake walls, holes for escape, double doors and various traps. This is the reason why the temple is also called Ninja (Spy) Temple.

This Iga-style Ninja Museum is located in Ueno, Iga City, Mie prefecture. Ninja is a kind of samurai warrior who engaged in espionage activities. Ninja House in the museum originally belonged to the local ruling family in Iga and was renovated and moved.

In Iga, people manufactured secret elixirs using medicinal herbs there, or they dispensed gunpowder. Thieves often broke in to steal the scrolls with the secrets of their production methods.

To deter intruders, many tricks were set up everywhere in the house so that it took longer for thieves to find the scrolls or escape. These tricks explain why the house is called Ninja House. The appearance of the house is like a typical thatched farmer's dwelling.

A visit to the house these days, includes demonstrations by Ninja actors who show the house's secret devices, like fake walls, trick doors and hiding places. Visitors to Iga Ninja House can experience the atmosphere of a former warlike period.