Beppu

  Beppu is a city on the northeastern corner of Kyushu, on the side of a volcanically active mountain.  More hot water gushes forth from these slopes in more varieties than any other place in Japan.  Some springs are turquoise while some have iron precipitates making the bottom red as below.  Others mix with soils to become bubbling mud.  The hot water is also used to keep crocodiles, hippos, and other foreign fauna alive for the entertainment of the Japanese who come to visit these springs.  Hotels are numerous and range from very inexpensive to exorbitant. The one geyser is topped off with a large rock so no one knows how high it could go if left in a natural state.
 

Chinoike Jigoku, or  "Blood Pool Hell," showing off its bright red coloring, is a favorite with the tourists and has a gift shop adjacent that is much larger than the pool itself.