It’s a bit out of the way so I didn’t see many other non-Japanese people there, but Showa Kinen Koen is well worth the trip out to Tachikawa. There are huge fields of poppies and rape blossoms, a lovely tulip garden, a Japanese garden, a bonsai area, and an incredible children’s playground. The children’s playground has giant, climbable dragon sculptures, rubber mountains for bouncing on, a water park, unicycle training area, and a “sea of mist”. The best time to see the flowers is late-April to early-May, so if you if you’re going to be in the Tokyo area around Golden Week, it’s well worth a visit. It’s on the Chuo Line about 30 minutes from Shinjuku. Click here for the park’s website.