Hama-rikyu is unique in Tokyo in having a large seawater pond which changes level with the ebb and flow of the tide. The pond is called Shioiri-no-ike, shioiri meaning "incoming tide". It is the only remaining seawater pond from the Edo era in Tokyo. The lock gates are opened and closed according to the water level in Tokyo Bay. Saltwater fish such as striped mullet, young sea bass, goby and eel inhabit the pond. There are also a number of wild birds, including black headed gulls and wild ducks. The pond is 28,000 square meters, which is almost 7 acres.
There are several artificial islands in the pond, called Konoji-shima (the Konoji Islets). The name “Konoji” refers to the Chinese character “Konoji" which means small. The islets are given the name “Konoji” because their arrangment in the pond resembles the shape of the character. The larger islet houses the Nakajima-no-ochaya tea house.
North side of the bridge showing a small island
Middle island