The park has the warm springs running through it. You can get spring water (bring containers). You can also get very reasonably priced whirlpool baths, roman bath and massage.
I tried the roman bath at $22. This is a private room with a tiled pool about 9 feet long and 3.5 feet wide. The pool is about 3.5 feet deep. The spring water is heated to 102 degrees. You get a towel and a pitcher of spring water. The pitcher of water is regrettably room temperature instead of ice water.
The floor in the room was covered with water. Bring shower shoes, The grout in the top tile and the feet of the plastic chair in the room had mold on them. A little chlorine bleach would take care of that.
It was great for someone who loves soaking in a hot bath.