Misasa Onsen's radium-rich waters are likely why it's been viewed as a "healing spring" for centuries. Though care should be taken when self-medicating with radiation (and medicinal or curative powers have not been evaluated by this website), Misasa Onsen has a number of wonderful public baths that are worth checking out if you're in the area. Among them is Kawaraburo (河原風呂), a public konyoku (mixed gender) bath tucked next to a river and near a bridge. In light of the bridge, it's not the most private place to bathe but don't let that stop you.
Nearby, a bath supposedly originated when hot water was found rushing out of a tree stump. Though the original stump is long gone, Kabuyu (株湯) has a large replica to indicate the history, and a wonderful old bathhouse with hot, dark water.
The town has its own onsen meguri circuit for those who want to bath-hop; about a dozen ryokans open their baths for non-guests, and you can don a yukata and meander about the quaint village from bath to bath.
Just about any kind of bathing is available here -- ryokans have private baths that can be reserved, there are family baths, large indoor and outdoor baths. It's got the works.
Misasa Onsen is accessible by bus; the nearest train station is Kurayoshi on the Sanin Main line.
35.4104947, 133.8930875
