For many years in the past, Koshigaya was known as a riverside city blessed with rich natural surroundings. The rivers and irrigation canals in the area include the Moto-Arakawa, Furu-Tonegawa, Ayasegawa, Niigatagawa, and Nakagawa rivers, (all of those are class A rivers by Japans standards), and the Kasai, Sueda, and Yakota irrigation canals are also located nearby.
Koshigaya is located about 30 km from central Tokyo, In December of 1996, Koshigaya became the sixth city in Saitama Prefecture with a population of 300,000. It has become one of the biggest cities in the southeastern part of Saitama Prefecture and is currently preparing itself for the twenty-first century by promoting safety, convenience, and comfort under the theme of a "A vigorous, culturally-oriented city that cares for its citizens and is blessed with ample water and lush greenery."
Information translated from the Koshigaya city homepage. (reworded to minimize Engrish).