According to the Kita-Tsuru Gun Shi (Records of Northern Tsuru County), there was a pond approx. 3 meters deep near the East Gate of Saiko-ji Temple. Otama, a housemaid at Ebisuya Inn, used to go to the pond and enter up to her waist. After the landlady of the inn scolded her for doing this one day, Otama placed a tub upside down on the ground and left the inn. Soon, clear water started welling up. The pond came to be called Otama-ga-ike Pond.
Otama is thought to have been the Dragon God and the guardian spirit of Nagamine Pond (Nagamine-no-ike Pond) near Otama-ga-ike Pond. Nagamine Pond was sadly destroyed to make room for the Chuo Expressway. Otama-ga-ike Pond is also dry with only a stone monument remaining.