Kitanomaru Park is a part of The Imperial Palace Outer Garden, and used be a part of Edo Castle. It is located north side of the Imperial Palace. Kitanomaru Park is an important woodland garden situated in the center of Tokyo. The park which continues on into the northern part of the Imperial Palace is planted with many broadleafed evergreen trees. There are Nihon-Budoukan and Science Museum in Kitanomaru Palace. You can enjoy wild life, fish and birds in the moats and New purification System.
Kitanomaru Park district was named after an area within Edo Castle called Kitanomaru. Prior to 1969, when Kitanomaru Park was opened, this district had been called Daikancho because many daikan (local governors) lived in the place soon after the construction of Edo Castle. This place was completely destroyed by the great fire in 1657. In 1875, Higashi-Daikancho (東代官町) and Nishi-Daikancho (西代官町) were established there. In 1878, these two neighborhoods were incorporated as a district named Daikancho. Today, the name Daikancho is known as an interchange of the Inner Circular Route of the Shuto Expressway. But even today there are two great gate from Edo Castle which still preserved in great shape.
Tayasumon Gate was situated at the northern part of the old Edo Castle. Before Edo Castle was constructed, this area was a rural district, called "Tayasudai." This is a typical Masugata-mon style of gate. The exact date of construction is unknown although according to some historic literature, this gate was already existed in 1607. The present gate was re-constructed in 1636, and is the oldest remaining gate in Kokyogaien National Garden.
Shimizumon Gate is the East gate of the Kitanomaru park, and it was rebuilt in 1658. Tayasumon Gate and Shimizumon Gate were designated as the Important Cultural Assets to Japan in June 1961, and because they are remnants of Edo Castle they are of great historical importance. Both gates are managed by the Agency for Cultural Affairs.