Hiroshima Castle is a National Historic Site located in Naka-ku, Hiroshima City, Hiroshima Pref. It was built in 1589 by Mori Terumoto, who had an intention of expanding his territory from the mountain area to the plain land. He selected the delta area at the mouse of the Otagawa River as the place to build a new castle, which should be used as the bases of the Mori clan with 1.2 million koku. Being built as the residence of the most powerful daimyo in the western Japan, the donjon was so magnificent as to have five stories and the two three-story attached wings. After the Battle of Sekigahara, the Mori clan, which sided with the West Army, lost three of the five esteem provinces, and Fukushima Masanori, a retainer of Tokugawa Ieyasu, was given the fief of Hiroshima instead. Masanori was, however, accused of having repaired the castle without notice and transferred to another fief. The castle was then resided by Asano Nagaakira and his clan till it was abolished after the Meiji Restoration. The donjon had been designated as a National treasure, but completely destroyed by the atomic bomb in 1945. The castle area is now arranged into Hiroshima Central Park, where the donjon was restored.