Unzen Onsen

A spa town with two histories

Legend dates the opening of Unzen to 701, when the priest Gyōki is said to have founded Onsen-san Manmyō-ji on the steaming plateau at the heart of the Shimabara Peninsula. For nearly a thousand years the site was a mountain temple complex with adjacent springs; it became a regulated bathing town only in 1672, when the Shimabara lord Matsudaira Tadafusa appointed an official yumori (spring keeper) to manage the waters.

Between those two dates fall the years Unzen does not advertise on its postcards. From 1627 to 1632, the same boiling vents that now run through the centre of town were used by the Shimabara domain to torture Christians who refused to recant. Victims were doused with scalding spring water, or thrown into the pools in front of family. Thirty-three are recorded as having been killed at Unzen Jigoku; twenty-nine of them were beatified by Rome in 2007. A simple cross above the boardwalks marks the site.

In 1934, Unzen became the centrepiece of Japan's very first national park (extended in 1956 to include the Amakusa islands and renamed accordingly).

Sulfurous steam and a cool plateau

Unzen sits at roughly 700 metres above sea level, on the saddle between the peaks of the volcanic Unzen range. The town itself is built around the Unzen Jigoku ("Unzen Hells"): an open field of sulfurous fumaroles, milky hot pools, and hissing steam vents, crossed by wooden boardwalks that take about forty minutes to walk end to end. The smell of sulfur is unmistakable, and on cold mornings the entire centre of town vanishes into white steam.

The altitude is also why Unzen became a summer retreat for foreigners in the Meiji and Taishō eras. After the North China Daily News published a piece on the springs in 1889, Shanghai-based Westerners began arriving by ship from Nagasaki; by 1913 the town had a golf course and tennis courts to entertain them, and the cool, dry summers earned Unzen the nickname "the Karuizawa of Kyushu" in foreign guidebooks.

The volcano next door

The Unzen range last erupted from 1990 to 1995. On 3 June 1991, a pyroclastic flow from Fugen-dake killed forty-three people, including the volcanologists Katia and Maurice Krafft and Harry Glicken. The eruption built a new lava dome, Heisei-shinzan (1,486 m), now the highest peak in the range and visible from the Nita Pass ropeway, which lifts visitors above the plateau for views over the Ariake Sea and, in late October and early November, the most photographed autumn foliage on Kyushu.