The name derives from a inlet of Hakata Bay formerly called "Kusagae," which was utilized as the outer moat (Oohori) of Fukuoka Castle when Kuroda Nagamasa, the first feudal lord of the Fukuoka domain, constructed the castle during the Keichō era.
Landscaping work was undertaken in conjunction with the 1927 East Asia Promotion Exposition, and the park opened in 1929 as a prefectural facility—Ōhori Park. With a total area of approximately 39.8 hectares and a large pond occupying roughly 22.6 hectares at its center, it stands among Japan's foremost water landscape parks.
In 2007, it was registered as a National Historic Site (scenic area).
The approximately 2-kilometer loop path around the pond is a popular jogging and walking course, with facilities such as a wild bird forest, children's playground, Noh theater, Japanese garden (covered separately), and the Fukuoka City Art Museum scattered throughout.
On the central island, connected by four bridges, stands the vermillion "Ukimidō," which has become the symbol of the park.
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