We both had to scrunch up to fit inside, but the cedar gave the steam a nice smell. There is a large boiling spring at one end of it in which all of the rocks are coated with yellow sulfur. From this area some of the water runs down a gradual rocky slope, giving off steam and killing everything it touches. There is no plant life among these rocks, not even a speck of moss. Most of the water, though, goes into a chain of old wooden filtration boxes that are elevated a few feet above the rocky ground.
Olfactory evidence remains.
The fall keeps the pool churning, and there is steam billowing off of it constantly. This hellish landscape, about 100 meters long and perhaps 15 wide, is encircled by a balustraded sidewalk with park benches and gazebos. We browsed the surrounding souvenir shops and had lunch in a restaurant nearby. Perhaps because the water is not quite boiling, the egg cooks very slowly, with the strange result of a nearly-solid yolk floating in a runny white that resembles semen. You're supposed to crack the egg into a cup and flavor it with a dash of sweetened soy sauce.