A large pond is located in the middle of the garden and visitors can walk around the pond.
This is the typical style for a garden of a federal lord in the Edo Age.
Such a garden of a federal lord at their mansion is called a "Daimyo-Teien" Garden in Japanese.
Tall office buildings are surrounding the garden. This scenery is a good combination of modern Tokyo and historical Edo. You will see the Tokyo Tower to the west.
In the Edo Age, Shiba-Rikyu Garden was along the coast. Sea water was introduced to the garden pound through a driving channel. The channel remains from the Edo Age.
If you walk around the pond in "Shiba-Rikyu" Garden, you will see "Kyudaitei" shown in the below right picture.
"Kyudaitei" is a small hill and used to be a sand hill on a beach.