The Call of Kyushu

Despite lush landscapes, hundreds of hot springs, and a recent wave of high-design hotels, this Japanese island rarely gets top billing. Danielle Demetriou travels by train (and ferry) to see what we've been missing.

- Danielle Demetriou, Hannah Walhout

FOR THE THIRD time in 15 hours, I lowered my body into a hot spring on the slopes of a volcanic peak. During my first dip, the previous day, the sun was glinting off the water; the second soak unfolded beneath a nearly full moon. This time, my pre-breakfast bath was shrouded in morning mist and steam.

The urge to spend almost every second immersed in water is impossible to resist at Kai Yufuin (hoshinoresorts.com; doubles from $187), a new ryokan resort on the island of Kyushu. Japan is known for its hot springs, or onsen, many of which have adjoining bathhouses or inns and Kyushu is home to more than a third of them.

The volcanic landscapes that heat Kyushu's springs also give the region its citrus groves and a saw-toothed coastline flecked with emerald islets. But despite the natural beauty and seductively laid-back tempo, the island is often overlooked by visitors from overseas. On a recent trip from my home in Kyoto, not long after Japan began opening up to international tourism, I saw firsthand what awaits travelers-including a flashy new bullet train that helps shorten the trip between Fukuoka and Nagasaki, two of the island's main cities, to 80 minutes.