Opening April 20, the museum is located on the grounds of Odawara Castle, a 15th-century landmark about 80km (50 miles) southwest of Tokyo. The site is easily reached from that city by a short train ride, along the same route that leads to popular day-trip destination Hakone.
During the tumultuous Sengoku period of the 1500s, Odawara Castle belonged to the powerful Hojo clan, who employed Fuma ninja to carry out assassinations, acts of espionage, and other covert operations.
At the museum, that story is told with videos, illustrations, wall text, and artifacts such as tools and weapons.
Activities geared toward children let mini ninjas hop across lotus leaves on a pond and sneak through a trick house with secret passageways and hidden compartments.
In the last room, an interactive video game teaches players to hurl virtual throwing stars (not real ones—don't worry) with deadly accuracy.

(Odawara Castle Ninja Museum)
Admission to the Odawara Castle Ninja Museum is 300 yen (US$2.68) for adults, 100 yen (US$0.89) for kids.