Tamachi Station Area

Outside of my own budget range, the upmarket Pullman Tokyo Tamachi Hotel is definitely up high on the list with it being very close to JR Tamachi (Yamanote line) station as well as at least two smaller parks with charming children’s facilities; Honshiba park and Shibaura park.

This area has more economical lodging options also for anyone with similar requirements with a lower price tag.

Worth checking out if Shibaura House has any events on that coincide with your stay. It’s a wonderful community centre which occasionally runs workshops for children and hosts farmers’ markets, they have a Facebook page for anyone interested.

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And another contender is the South Ebisu area, it has a newish hotel
https://www.holichotel.jp/en/ebisu/room/
and a newly renovated toddler’s area in the nearby Ebisu Minami 2 park (Pig Park) which has grass in the play areas rather than the standard skin shredding gravel.
https://kids-rurubu-jp.translate.goo..._x_tr_pto=wapp

And to mix it up a bit, in case the older child is hankering for more challenging equipment, there is also Ebisu East Park, about 4 blocks to the North East of Ebisu Station.
There’s also Kageoka Park, which has a small but well designed climbing frame and slide combo, this is adjacent to Yebisu Garden Place. Also next to Yebisu Garden Place is Ebisu Minami 1 Park (squid park).