Mount Kōya
Ninkan is believed to have established the Tachikawa lineage while in Izu. One of the Tachikawa-ryū's critics, a monk from Mount Kōya named Yūkai (, 1345-1416), writes in his "Hōkyōshō" (宝鏡鈔, "Compendium of the Precious Mirror," 1375):