Travel Reference
In-Depth Information
Boiling River's intensely hot source spring
The trail leads about one-half mile (0.8 km) along the river to the hot spring area. The
entire area is closed off until the water is low enough (usually in mid to late July) to make it
safe for bathing.
Hot River is an older but unofficial name used by scientists for this spot. The river does not
really boil; its temperature varies between 117 and 124°F (47-51°C) where the hot and cold
waters mix. One other approved swimming area is described on
page 50
.
Special Caution:
Be sure to keep your head out of the water entirely. The thermophilic
amoeba
Naegleria fowleri,
if ingested through the mouth or nose, can cause a type of fatal en-
cephalitis. The bacterium
Legionella pneumophila,
which causes Legionnaires' disease, is also
present in some of these thermal waters. Although there have been no reports of these dis-
eases in park personnel or visitors, it's wise to be careful.
3.1/2. 2
Montana/Wyoming state line. The boundary was inadvertently set approximately
1,200 feet (365 m) south of the 45th parallel, according to Yellowstone historian Aubrey
Haines.
Local residents called this steep hill “Soap Hill” when the road grade was 15 percent. Below
the hill in the 1870s was a short-lived establishment called McGuirk's Medicinal Springs,
where Matthew McGuirk dammed Boiling River and charged rheumatic customers to “take
the waters.”
