Shinobazu Pond - History and Changes

History and Changes

In the Jōmon period the entire place used to be just a cove of Tokyo Bay. Later, some centuries into the Common Era, the sea withdrew, leaving behind extensive marshes that covered most of the old Shitamachi. The pond is what remains of those marshes. We know that by the 15th Century the present name was already in use.

In 1625 the Edo Shogunate had the Kan'ei-ji built here as a counterpart to Hieizan's Enryakuji in West Japan. The temple's founder Jigen Daishi (Tenkai), liking Lake Biwa, had Benten Island built in imitation of Chikubushima, and then the Bentendo on it. At the time the island was accessible only by boat, but later a stone bridge was added on the east, making it possible to walk to it.

The pond's shape until the beginning of the Meiji Era was very different from now, in particular the northern part where the Ueno Zoo is, which was much wider. At the time, the Aizomegawa flowed into it. In 1884 however, a cooperative horse racing company, wanting to open a racing track, had the pond partly filled, bringing it to the present shape and size. The first horse race took place in the November of the same year in the presence of the Emperor, and until 1892 races took place every spring and summer.

In 1907 the Kangetsukyō Bridge (観月橋, Kangetsukyō?) was built toward the west in occasion of the Tokyo Industrial Fair, making it possible to walk across the whole pond. In 1929 more work divided the pond in four distinct parts. The boat rental business, which continues to the present day, was started in 1939. Today's Cormorants Pond is the result of the fusion of two of those four sections.

During World War II water was pumped out and the pond divided into rice paddies (the so-called Shinobazu Tanpo (不忍田圃, Shinobazu tanpo?). There was later, among others, a plan to build a baseball field on it, but in 1949 it was decided to return the pond to its original form which we still see today.

In September 1967 a hole was opened by accident in the pond during the construction of Tokyo Metro Chiyoda Line, and approximately 30 thousand tons of water flowed away.

In the years between 1990 and 1994, the city authorities installed water purification equipment.