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Old Faithful Inn

Circle of Fire Tour

Twilight on the Fire Hole

Photo Safari

Geysers

Animals

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One of Yellowstone's most intriguing aspects is its  thermal features that can be seen as the product of millions of years of geology at work. Much of Yellowstone sits inside an ancient volcanic caldera (the exploded crater of a volcano). The last major caldera forming eruption occurred over 600,000 years ago. For hundreds of thousands of years following that, subsequent lava flows slowly filled in most of the caldera. Even now, in some places, nearly molten rock resides as little as 2-5 miles below the surface. Heat from the volcanic activity makes its presence known by heating ground water and creating the thermal features seen in the Park. The four basic types of thermal features present in the Park are geysers, hot springs, fumaroles, and mudpots. Many of these are concentrated in Yellowstone’s major geyser basins: Upper, Midway, Lower, Norris, West Thumb, Shoshone and Heart Lake.  We visited some of these on our trip.

 

GEYSER VIDEO CLIPS

 

Old Faithful Erupts

 

Castle Geyser Erupts

 

Cliff Geyser