Ishiyama Honganji Site is in Osaka Castle Park, a 10-minute walk from Otemon on the south side of the honmaru. It traces back to Osaka Gobo, founded by Rennyo in 1496, and is known as the place where defenders opposed Oda Nobunaga for 11 years during the Ishiyama War. Large-scale Osaka Castle construction and Tokugawa-period rebuilding left no accurate boundaries or remains, so the site is identified on location by a stone monument and an information board. It sits off the main routes through Osaka Castle and is not easy to notice.