NicoNicoPark in Meiji Jingu Gaien.
NicoNicoPark (http://www.meijijingugaien.jp/english/park.html) is a nice park for small children. It's located in the old Olympic village in Meiji JIngu Gaien and is close to batting cages, the Olympic stadium, and the Yakult Swallows' Jingu stadium.
Nico
Argentina