Kokkai Zentei Western Garden (国会前庭 西洋庭園) is located in front of Japanese Parliament House. This western style garden was used to be the house of Ii clan. There is Tower clock which symbolizes the division of powers. In this garden, there is Memorial Museum of Parliament. There is also Tokyo Peil.
Tourist Info.
Admission for Memorial Museum of Parliament: Free.
Open: 9:00 to 17:00
Access
0. at Tokyo Station.
1. use Marunouchi Line to Kokaigijidomae.
2. walk south (5 min.)
30 min
New Wave Samurai Movie. 
映画好き集まれ！ 
The founder of Edo, Ota Dokan, wrote a poem at this place. Later Kato Kiyomasa and Ii clan built house in this place. There are dogwood which given by the United States.
Memorial Museum of Parliament
... is built in 1970 for the 80 years' anniversary of the Parliament. This museum displays the system and history of parliament. There is also experiencing room which you can listen the announcement of the prime minister at the congress hole.