Chinzanso Garden (椿山荘庭園) is a Japanese stroll garden attached to the Hotel Chinzanso Tokyo. In the Edo period, the place Chinzanso is now situated was a suburban house of a domain lord. When the feudal times ended, Yamagata Aritomo (1838-1922), one of the most prominent army general and politician of the Meiji era, constructed his residence here in 1878. He himself designed this garden, since garden designing was one of his interests. In 1918, it was obtained by an influential business leader as his villa, and after WWII, it was converted into a commercial facility, starting with a wedding center and later a hotel.
Though it is now part of a hotel, you can walk through the garden freely. Its entrance is on the footpath along the Kanda River flowing southwest of the garden. There are several restaurants along the pathway running though the garden. Because of the air raids in WWII, there are no buildings left which existed here before the war except for a three-story Buddhist pagoda, which was constructed in around the 16th century in Hiroshima Prefecture and relocated here in 1925. Other structures were moved or constructed here after the war.
It's an 8-min walk from Tokyo Metro Yurakucho Line Edogawabashi Station, or a 7-min walk from Toden Arakawa Line Waseda Station (not to be confused with Tokyo Metro Tozai Line Waseda Station).
Sekiguchi Bashoan (関口芭蕉庵) is a small garden next to Chinzanso. This is a spot where famous haiku master Matsuo Basho (1644-1694) lived for four years. After his death, this place was preserved by his followers to commemorate him. Present buildings are post-war reconstructions. Frankly speaking, there's not much to see here, but since it's adjacent to Chinzanso and along your way to Shin-edogawa Garden, you may as well take a look at it, especially if you're interested in haiku. Its main gate facing the footpath along the Kanda River is usually closed, and you need to get into the garden from a door on the west side of the site.
Adjacent to Sekiguchi Bashoan is Higo Hosokawa Garden.