Yasui Doton was in charge of construction of Osaka Castle. As a reward, he was given wasteland in which he invested all of his private money to excavate a river. After his death, his son, Doboku, carried on and completed this undertaking in 1615. This river was originally called South Horikawa, but was renamed “Doton-bori” by Tadaaki Matsudaira, Lord of Osaka Castle, in praise of Doton’s meritorious efforts.