Unzen-Amakusa National Park

Unzen-Amakusa National Park has two faces. On the Shimabara Peninsula east of Nagasaki rises Unzen, a cluster of volcanic peaks with fuming vents, hot springs and the Heisei Shinzan lava dome, born in the eruption of 1990–1995. To the south, across the Hayasaki Strait, lie the islands of Amakusa, a coastal landscape of islets, cliffs and bays in Kumamoto Prefecture, with a small part in northern Kagoshima.

On 16 March 1934 Unzen became, together with Setonaikai and Kirishima, one of Japan's first three national parks; it is traditionally listed first. Its hot-spring resort had already attracted Westerners from Shanghai and Hong Kong in the late 19th century, and it became Japan's first prefectural park in 1911. Amakusa was added in 1956, and the park took its present name.

The region is also marked by history: both Unzen and Amakusa were centres of early Christianity in Japan and of the persecution and rebellion that followed, and the Shimabara Peninsula was among the first UNESCO Global Geoparks in Japan.

Unzen is a composite volcano built on a graben, a sinking block between faults that cuts across the Shimabara Peninsula. Its main peak, Fugendake (1,359 m), was overtopped by Heisei Shinzan (1,483 m), a lava dome that grew between 1990 and 1995 and repeatedly collapsed into pyroclastic flows. In 1792 an earthquake triggered the collapse of Mayuyama above Shimabara; the landslide and the tsunami it caused across the Ariake Sea killed some 15,000 people, remembered as 'Shimabara taihen, Higo meiwaku'.

Unzen Jigoku, the 'hells' above the hot-spring village, are fields of steam vents, boiling pools and sulphur deposits. Amakusa, by contrast, is built of sedimentary rocks, including Cretaceous and Palaeogene strata rich in fossils, cut by the sea into a drowned coastline with some 120 islands; the western coast of Amakusa-shimoshima faces the East China Sea with high cliffs.

Unzen's slopes carry a sequence from evergreen forest to deciduous woodland and scrub, famous for mountain azaleas in late spring and for rime ice in winter. The bare surfaces left by the 1990s eruption are being recolonised, offering a natural laboratory of plant succession. Around Amakusa, rich coastal waters support a resident population of dolphins.

In the 16th century the Shimabara Peninsula and Amakusa were among the most Christian regions of Japan, with a Jesuit college at Amakusa. After Christianity was banned, believers were tortured and executed in the boiling springs of Unzen Jigoku in the late 1620s and early 1630s. Heavy taxation and persecution led to the Shimabara-Amakusa Rebellion of 1637–1638, led by the young Amakusa Shirō, which ended in the massacre at Hara Castle.

In the Meiji era, Unzen Onsen became an international summer resort for foreigners from treaty ports and colonial cities in East Asia. The 1990s eruption, which killed 43 people on 3 June 1991, including the volcanologists Katia and Maurice Krafft and Harry Glicken, made Unzen a centre of volcanic disaster education.