|  Sign at entrance to Yellowstone National Park
 |  Lewis Falls
 |  Yellowstone Lake
 |  American buffalo (bison) on the plains at sunset
 |  Bison in the setting sun
 |  Our cabin at Island in the Sky, Idaho
 |  West Yellowstone, Montana
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|  Ice falling from the roof at the gas station
 |  On the Madison river in Yellowstone in the morning
 |  On the Madison river in Yellowstone in the morning
 |  On the Madison river in Yellowstone in the morning
 |  In the Terrace Spring area
 |  Heat and cold in the Terrace Spring area
 |  Hot and cold in the Terrace Spring area
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|  In the Terrace Spring area
 |  In the Terrace Spring area
 |  Bacterial growth in the water in the Terrace Spring area
 |  In the Terrace Spring area
 |  The boardwalk in the Terrace Spring area
 |  On the boardwalk in the Terrace Spring area
 |  Gibbon Falls
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|  Downstream of Gibbon Falls on the Gibbon River
 |  Gibbon Falls
 |  Gibbon Falls
 |  Bison
 |  American Buffalo (bison)
 |  Bison
 |  American Buffalo (bison)
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|  Through the Golden Gate Canyon to Mammoth Hot Springs
 |  Through the Golden Gate Canyon to the Mammoth Hot Springs area of the park
 |  A basin of volcanic activity near Mammoth Hot Springs
 |  Steam rises over the geyser plane next to Mammoth Hot Spring
 |  Viewpoint over Mammoth Hot Springs
 |  Fort Yellowstone, Mammoth Hot Springs
 |  Fort Yellowstone, Mammoth Hot Springs area of Yellowstone NP
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|  On the Mammoth Terrace Drive
 |  Steam and snow, Mammoth Terrace Drive
 |  Result of a mix of hot water and cold air
 |  Orange Spring Mound
 |  Orange Spring Mound
 |  Orange Spring Mound
 |  Orange Spring Mound
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|  Travertine terraces along Mammoth Terrace Drive
 |  White Elephant Back terrace
 |  Steam and snow, Mammoth Terrace Drive
 |  Steam and snow, Mammoth Terrace Drive
 |  Seen from Mammoth Terrace Drive
 |  Terraces at Mammoth Hot Springs
 |  Hillside at Mammoth Hot Springs
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|  Steam from a vent on a snow covered hill
 |  Driving through Yellowstone
 |  Fly fishing in the morning
 |  An area of underground activity
 |  Fly fishing
 |  Just in time arrivial at Old Faithful Geyser
 |  Old Faithful in the initial stages of eruption
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|  Old Faithful building up steam
 |  Old Faithful geyser
 |  Old Faithful geyser, Yellowstone NP
 |  Old Faithful geyser towards end of eruption
 |  Old Faithful geyser after eruption
 |  The Old Faithful Inn
 |  An opening into the Underworld, Black Sand Basin
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|  Hot Spring, Black Sand Basin, Yellowstone
 |  Black Sand Basin
 |  Black Sand Basin
 |  Black Sand Basin
 |  Seen in Black Sand Basin
 |  Bacterial stream, Black Sand Basin
 |  A geyser basin
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|  Starting out on the Fountain Paint Pot trail
 |  Bacterial pool
 |  From the Fountain Paint Pot trail
 |  From the Fountain Paint Pot trail
 |  Fountain Paint Pot mudpot
 |  Red Spouter
 |  Evening sun through the rising steam
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|  Sream emanating from a vent - Fountain Paint Pot trail
 |  From the Fountain Paint Pot trail in the evening
 |  Turning back on a slippery Fountain Paint Pot trail
 |  Walking on a slippery Fountain Paint Pot trail
 |  Near sunset from Fountain Paint Pot trail
 |  From the Fountain Paint Pot trail
 |  Sunset as we depart Fountain Paint Pot trail
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