I've been there for quite a few times.
I would recommend people to go during non-public holidays.
The first time I've been there was a public holiday. The water seems to be dirty, however I went upstream where the water is really clear and nice to soak in..
And you'll see a lot of people soaking in the hot spring water, which you might not get the chance to squeeze in.
The second time I went was with my friends. It wasn't a public holiday.
So there were not as much people as I've seen during public holidays.
The water is so clear and warm. And it's so relaxing there, that you don't have to squeeze with people. =D
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