Travel Reference
In-Depth Information
Firehole River is one of two places in the park where swimming is permitted.
Compared to the much smaller Midway Geyser Basin, the Lower Geyser Basin is
enormous, spanning 12 square miles and including several clusters of thermal features.
Among them are the notable
Fountain Geyser,
a placid blue pool that erupts without warn-
ing for an average of 20 minutes and sprays up to 50 feet high, the temperamental
White
Dome Geyser,
the almost-constant
Clepsydra,
and the
Pocket Basin Mud Pots,
which are
the largest collection of mud pots in the park.
Great Fountain Geyser
in the Firehole Lake
area is the only predictable geyser in the Lower Geyser Basin and erupts every 9-15 hours
at heights of anywhere between 75 and 220 feet.
