Eagleville hot spings in Cali is close, about 1 hour south from the main freeway once your out of the reserve.

Fisher hot springs is a the base of hart mountain on the east side, you go on a dirt road from adell.

Bog Hot is about 2-3 hours east and is a hot river

There are some others but these are the closest.

Hart mountain is a nice spot. I was there when I was REALLY early spring and stil blowing some snow. The spring was hot but could have been warmer. Totally hot enough to soak and might get hotter when the air temp at night is above 20 degrees.
There are a few pics on my blog of it.
There is a man made wall around the springs with a concrete deck but the spring itself is just an open crack in the rock.
There are also some smaller pools out in the meadows, might need a little digging.

It was a sweet weekend for me, nice getting out of a freezing tent and damp bag at 4 am and soaking till the sun came up.

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