If by chance, you are visiting Tokyo in November, you should definitely check the Gingkos all over the city.
The Gingkos trees are very popular in Tokyo, especially during Autumn, why? Simply because their leaves turn into yellow/red colors and will give you a perfect autumn atmosphere. You can see them in most of the parks (Shinjuku Gyoen, Yoyogi Park, Ueno etc) and you might experience a festival celebrating the famous tree with stands and animations.
One of these festivals I would recommend is the one held in MeijiJingu Gaien, not far from Sendagaya Station. You can check their website below to check the exact location and for further informations. (Starting from November 14th until early December).