 The actual construction work on Morioka Castle was supervised by his Nanbu Nobunao's son, Nanbu Toshinao, who later became the 1st "daimyō" of Morioka Domain, but the castle was not completed until 1633, during the tenure of Nanbu Shigenao, the 2nd "daimyō".However, its three-story "tenshu" burned down only one year later, and was never rebuilt.In 1906, the site was opened to the public as Iwate Park, with gardens laid out by modern park designer Yasuhei Nagaoka, and are a popular spot for viewing the sakura blossoms in spring.