You'll want to grab an (english language) map upon entering this large park that stretches across Shinjuku and Shibuya. There is a lot of ground to cover here.
The park is split into gardens of three distinct styles: French formal, English landscape and Japanese traditional. Not surprising the Japanese section is the most interesting and beautiful with waterlily ponds, artfully trimmed bushes and statues. The nearby Taiwan pavilion is an elegant spot for photos.
The original gardens date back to 1906, but were destroyed and rebuilt after the war. The diverse and well manicured gardens are great for wandering, taking photos or having an afternoon picnic. The garden has over 1500 cherry trees trees that burst into vivid blooms in late March or early April. It's a favorite spot for blossom viewing and can be very crowded during those times.