Once the Mori family secured possession of 9 provinces of ancient Japan in western Honshu, Terumoto Mori built Hiroshima Castle on the Ota River delta in the center of their lands. This flatland castle was constructed in 1589 and was the largest in western Japan at the time. The area at the fork of the Ota River was called Koi-no-ura (Carp Inlet) so the castle was nicknamed "Carp Castle" or Rijo in Japanese.

The Mori family did not rule for long from the castle. They and their allies lost the battle at Sekigahara (1600) in Shimonoseki, Yamaguchi Prefecture, and they lost all of their lands except those in Yamaguchi Prefecture.

The castle passed to a number of different rulers and survived until the Meiji Era. It was named a national treasure in 1931.

The castle was completely destroyed by the atomic bomb in 1945. It was rebuilt in 1958 using concrete and now houses a small museum with artifacts from Hiroshima's past. The outer facade is a close approximation of the original. Strolling through the castle grounds is a relaxing break from the city bustle. The grounds contain one of Hiroshima's best cherry blossom viewing area.

Hiroshima Castle is north of Hiroshima Municipal Stadium where the Hiroshima Carp play. The route from JR Hiroshima Station is well marked with signposts in English and Japanese. There is no parking for cars at the castle. The castle is close to the Shukkeien Gardens.

See also: Himeji Castle and Hiroshima's History