- Gangi-zaka slope
Shimizu-mon gate 
@Crossing a small bridge leads to the Shimizu-mon gate which is the east gate of the Kitanomaru district. This gate is also a Masugata-mon style gate which has a piazza in a square form. Passing through the Korai-mon gate and the Yagura-mon Gate (meaning the gate with a keep) and turning to the left, you will see the Gangi-zaka slope standing in your way, which keep the shape just as it was in the Edo era. We call this slope gGangi-zakah, because the shape of the slope with stairs high and wide looks like a group of flying geese in a procession.
@The period of the establishment of Shimizu-mon Gate, it is obscure, but there was some historic literature that Shimizu-mon Gate existed already in 1620 and it was rebuilt in 1658. This Gate and the Tayasu-mon Gate were designated as the Important Cultural Assets to Japan in June 1961, because they are remnant of Edo Castle they are of great historical importance, and these gates are managed by the Agency for Cultural Affairs.