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Old Faithful
Area Tour

List of

South Section
Interactive Map

North Section
Interactive Map

Fan & Mortar Geysers

Mortar Geyser spouts off alongside the Firehole  River.Fan and Mortar Geysers are in close proximity to one another and almost always erupt in concert. The interval between eruptions ranges from 1-1/2 days to months. Most eruptions last about 45 minutes. Mortar Geyser, pictured here, erupts to heights of 40 - 80 feet while Fan can reach heights of 100 - 125 feet.

Old Faithful Area Tour

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