Edo Castle Outer Moat Underground Museum

The outer moat of Edo Castle used to encircle much of central Tokyo. Today, apart from a few remnants between Akasaka and Iidabashi, it is mostly filled in. This tiny museum—more a memorial—displays a big chunk of the original wall of the moat.

The small gallery can be accessed via the stairs descending from exit 11 of Toranomon Station on the Tokyo Metro Ginza Line. The station entrance is directly in front of the land mark Kasumagaseki Building, adjacent to Sotobori-Dori Avenue.

Although there isn’t much information available in English, you can admire the workmanship of the Edo-period stonemasons and look for the distinctive marks on some of the stones that indicate the daimyo (feudal lord) that donated the rock for the wall of the moat. The bottom of the observation window facing the wall, marks the original water level in the moat.

Aside from the gallery, there are other remnants of the moat wall in the area. One is across the road, another is to the left of the gallery (when facing the Kasumigaseki Building) and yet another is in the courtyard of the neighboring Ministry of Education building which is open to the public.