Obama Onsen

Obama is not a famous name in Japanese tourism, which is partly why it is worth the effort to get there. From Nagasaki Station you board the train toward the Shimabara Peninsula, and the journey out to Obama takes you along the edge of Tachibana Bay, where the water is a very particular shade of deep blue and the Mount Unzen volcanic group rises directly inland. The town is set right on the water's edge, which means when you arrive on foot and look east, you see the bay, and when you look west, you see steam rising from the ground in about thirty different places simultaneously.

The spring water at Obama comes from roughly 30 sources, with a combined output of more than 15,000 tons per day at 100 degrees Celsius. The hottest vents push past 105 degrees. The water is geothermal and deeply saline, and the steam it produces pervades the whole lower town, seeping from cracks in walls, rising from drains, and curling off the surface of the ocean where subsurface vents heat the shallows near the shore. The actual bathing water, drawn down and mixed to a usable temperature, is clear and heavy with sodium chloride. It coats your skin with a fine salt film when you step out, and the retained warmth stays with you for a long time.

Obama's standout feature is Hot Foot 105, a public foot bath built directly in front of the sea. It is 105 meters long, which makes it Japan's longest foot bath, and the number 105 also references the source temperature in degrees. The wooden benches run along a raised channel of hot water facing the bay, and on a clear afternoon you can sit there with your feet in the water and look directly at the sun going down over Tachibana Bay and the dark outline of Kyushu beyond. The experience costs nothing.

Near the foot bath, stone steam cookers called mushigama sit over the vents, and visitors rent baskets from the hut nearby to cook vegetables and eggs in the geothermal steam. This is not a theatrical performance for tourists. It is a practical use of ground heat that locals have relied on for generations. The town documented its springs as far back as 713 AD in the Hizen Fudoki, and in December it hosts an annual fireworks display over the bay that draws locals back year after year, not for the onsen but for the sky.