Tokugawa Ieyasu, the first Tokugawa shogun, was given the Kanto Plain region in 1590 and made the little town of Edo his seat. According to tradition, he often hawked near here and particularly liked tea made from the water of this spring, so he named it "Ocha-no-mizu" (tea-water).
As Ieyasu's capital, Edo, the present Tokyo, had a rapidly growing population, and lack of water became a problem. By 1629 waterways were made for bringing water from here to Edo via the Kanda River.
The spring is in Inokarshira Park in Kichijoji, the junction of the Chuo Line, which goes west from Tokyo Station and Shinjuku Station, and the Inogashira Line from Shibuya.