Iga has given birth to the Iga-ryu Ninja sect in the 12th century, and ninja used to train in Ueno. In he late 16th and early 17th century, the rebellion of Tensho Iga against one of Oda Nobunaga's sons saw the almost anihilation of the Iga ninja. The Ninja Yashiki Museum shows demonstration in martial arts, a ninja residence (with secret hidding places) ninja equipment and weaponry.
The Ueno castle was built in 1608 by lord Todo Takatora, but the present structure is a 1935 reconstruction. The 30m high surrounding walls are said to be the highest in Japan.