Photo: 釣ちごちゅが at Japanese Wikipedia / CC BY-SA 3.0 · Wikimedia Commons
Saikai City
Nagasaki Prefecture · City
Official websiteNagasaki Prefecture page
Saikai City consists of the northern part of the Nishisonogi Peninsula and surrounding islands, and its coastline is a complex ria coast. Saikai Bridge spans the Hario Strait, which connects Sasebo Bay and Omura Bay, and whirlpools can be seen there. Tourist spots include Nagasaki Bio Park and the Nanatsugama Limestone Caves.
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
Amusement parkNagasaki Holland Villageamusement park in Nagasaki, Japan
BridgeSaikai Bridgebridge in Japan
ZooNagasaki Bio Park- IslandHira Isalandisland in Gotōnada, Nagasaki, Japan
IslandMatsu Islandisland in Gotōnada, Nagasaki, Japan
BridgeOshima Bridgebridge in Nagasaki, Japan- IslandEnoshimaisland in Gotōnada, Nagasaki, Japan
Roadside station (Michi-no-Eki)Michi-no-Eki Saikairoadside station in Saikai, Nagasaki prefecture, Japan
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
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 Nagasaki Prefecture
The description was written for this site, picking out representative features.