Tsuwano puts its geothermal gifts to good use at the spa at this hot spring. Inside and out, the tubs have great views of the surrounding gumdrop-shape volcanic peaks. It's west of everything else in town, across the river from the Washibara Hachiman-gu (a shrine where traditional horseback archery contests are held the second Sunday of April every year), but still not too far to get to by rented bike. Note that the hot springs are closed the second and fourth Thursday of the month.
256–O-aza Washibara, Tsuwano, Shimane-ken, 699-5613, Japan