Photo: Sander van Malssen / CC BY-SA 2.0 · Wikimedia Commons
Kasaoka City
Okayama Prefecture · City
Official websiteOkayama Prefecture page
Kasaoka City in southwestern Okayama Prefecture faces the Seto Inland Sea, with the 32 Kasaoka Islands offshore. The city is a breeding ground of the horseshoe crab, a "living fossil," and has the Horseshoe Crab Museum. The Shiraishi Odori dance of Shiraishi Island and the farms on the vast reclaimed land of Kasaoka Bay are also features.
Key facts
Source: Statistics Bureau of Japan, 2025 Population Census (population, area and density); area from the Geospatial Information Authority of Japan (GSI), Area Statistics of Prefectures and Municipalities (2025). National ranks are among the 1,741 municipalities, ordered by this site from these values.
Live information
Current weather (observed)
Places to visit
Chosen automatically, most popular first, from landmarks and cultural properties registered in Wikidata (we have not checked whether each is open). Names and descriptions: Wikidata (CC0); photos: Wikimedia Commons (photographer and license under each photo).
National parks in this city
- Setonaikai National ParkTotal park area 673 km²Spans Hyogo, Wakayama, Okayama, Hiroshima, Yamaguchi, Tokushima, Kagawa, Ehime, Oita
Chosen by overlaying the park boundaries (Ministry of the Environment, Biodiversity Center of Japan, "National Park Areas" GIS data, updated April 28, 2025, combined and simplified by NIPPON ATLAS) with municipal boundaries (National Land Numerical Information, January 2021), keeping overlaps of about 0.5 km² or more (approximate). Areas are the land areas from the Ministry of the Environment, "Overview of National Parks" (April 10, 2026). All national parks
Neighboring municipalities
Municipalities sharing a boundary (computed from the National Land Numerical Information administrative boundaries, January 2021).
Other municipalities in Okayama Prefecture
The description was written for this site, picking out representative features.