• View from the Norris Geyser Basin (looking west)
National Park ID,MT,WY  Fumaroles and How They Work  A fumarole
emits a jet of hot steam in Porcelain Basin.  Fumaroles, or
steam vents, are the hottest hydrothermal features in the park.
They have so little water that it all flashes into steam before
reaching the surface. At places like Roaring Mountain, the
result is a lot of hissing of steam and gases.  Black Growler
Steam Vent  Norris Geyser Basin  Did You Know?  Fishing Bridge.