Shimizu Gate and Ushigafuchi Moat (清水門・牛ヶ淵) 清水門
One of only three surviving gates of Edo Castle: a cultural property since 1961.
The north-east corner of the imperial grounds, between the Ushigafuchi moat and the Shimizu Gate of the Kitanomaru. The Shimizu moat, which the same sources mention, is the stretch of water just below the gate.
Tokyo
Kudanshita, Takebashi
Suzume
This is the view with which the film opens the worm's Tokyo sequence, with the golden onion of the Budōkan rising above the trees.