One of Tokyo's best parks, Inokashira-kōen has a big pond in the middle flanked by woodsy strolling paths. A highlight is Inokashira Benzaiten, a shrine to one of Japan's eight lucky gods. (Benzaiten is actually the octet's sole goddess; she's also the Japanese incarnation of the Hindi goddess Sarasvati and a patron of the arts). On weekends look for musicians, puppeteers and other assorted performance artists around the park, as well as lots of Tokyoites of all ages.
You can rent row boats (¥700 per hour) and swan-shaped pedal boats to take out onto the water (¥700 per 30 minutes).
To reach the park, walk straight from the Kōen exit of Kichijōji Station, cross at the light and veer right at Marui (‘0101’) department store; the park is at the end of the lane.