Tokyo is very hot and humid during summer, and it is not so cool in the morning and evening because there are a lot of skyscrapers and paved roads which absorb the heat. However, you can escape from this heat with a visit to Todoroki Valley. When you go down to the bottom of the valley, you will notice a big drop in temperature. Todoroki Valley is located near Todoroki Station on the Tokyu Oimachi Line in Setagaya ward.
In the mid of July, we hiked down the stairs located at Golf Bridge (there used to be golf course here in 1930), and it was much cooler at the bottom of the valley than up above, since the tall trees on both sides of the Yazawa river block out the sky and hot sun. I only felt sunbeams streaming through leaves instead of strong direct sunlight. I've heard that the temperature at the bottom is generally lower by 3-4℃. It was like another world: I was surrounded by deep green trees, and I breathed fresh and cool air. I enjoy walking along the river and listing to birds singing. Also, I saw some people taking photos of all the beautiful nature.
Then, we went to Todoroki Fudo Temple after passing in front of the small Fudo waterfall, surrounded by some beautiful Buddhist statues. The fall has been venerated for centuries, and used by Buddhist followers for meditations. The temple, which has a 1500 year history, is famous for sakura, or cherry blossoms. I want to come back here to see sakura next spring, from late March to early April.
We continued to walk and found a traditional house, Syoin-tsukuri in the Japanese garden. We took a rest on a bench under the roof of the house, and there were some panels which introduced its history and geographic information in Japanese.
Todoroki valley is 1 km long, so it is short and easy to walk, but some parts of the path along to the river are muddy and slippery. I recommend that you wear suitable shoes. It's a great place. Enjoy!