Hirauchi Kaichu Onsen (Underwater Hot Spring)

Beautiful rotenburo (outdoor onsen)! Views are great, the temperature of the different pools vary, so you should find one that's just right. Make sure you check the times for low tide and remember this one's a mixed bath and no swimsuits allowed. Women can wear a bathing towel (like a cloth dress), see photo. Honestly, it's a little intimidating being so exposed as the path to the onsen is elevated so people can see you from 50m away and there are a few occupied houses in very close proximity, but if you can get past that, it's great!

Very cool place. Highly recommend. The low tide that day was around 2pm; we went around 4:30pm and it was still very good. Almost everyone was local. No one was wearing swim suits, but all the men and women were using towels to cover their bodies. I unfortunately didn’t bring a towel, so I went in fully naked… The people were respectful, but I was worried that I offended them… oh well. Before you go in, grab a little basin and wash yourself with the water from the two smaller pools.

Lowtide twice a day, come within before or after 2 hours of lowtide(check before hand). Lots of lil critters and crabs crawling the place, if creepy crawlies aren't your thing maybe try the other osen nearby. Multiple baths with different water temperatures very scenic

I didn’t end up going in as it was (a) too hot a day and (b) only men there when I went. But it looked like it would have been nice

Nice place, I was the only one in so can take photos. There are four basins. Two large and two small. Each of which are quite hot. Please be careful when step in as the bottom is very slippery.

Really beautiful spot to relax and to take a hot bath. We went at 1 p.m and the tide was low so we were quite lucky to be the only ones there for most of the time. Unfortunately there was a group of tourists not following the rules, taking pictures and going in fully clothed without rinsing themselves. Sad to see, as the few rules a clearly visible at the entrance. Just follow these rules and respect the culture!!!

Very nice natural hot spring. Easily accessible by car. It says everywhere that swimwear is prohibited, but almost all women where wearing it together with a towel. All men bathed naked, but to bring a small towel seems to be the thing to do, to slightly cover yourself when sitting on the side to cool down, or walking around.

The bathing experience was nice, especially if it's raining a bit. You get nice views of the mountains and of the sea. It can get quite crowded and I was annoyed by some locals not respecting the rules and wearing clothes which made me feel quite uncomfortable considering I made the effort to be completely naked