Cliff Geyser erupts from geyserite bank on edge of Firehole River through Black Sand Basin, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America (U.S.A.), North America

Eruption of Riverside Geyser seen from Firehole River bridge, Upper Geyser Basin, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Rainbow cast by eruption of Riverside Geyser, Firehole River, Upper Geyser Basin, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Elevated view of Doublet Pool, Firehole River and Castle Geyser, Upper Geyser Basin, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Eruption of Riverside Geyser, Firehole River, Upper Geyser Basin, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

American Bison (Bison bison), Little Firehole River, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Bull elk near Firehole River, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Hot Springs emptying on the Firehole River, Wyoming, United States of America, North America

Hot Springs emptying on the Firehole River, Montana, United States of America, North America

Elk, Firehole River, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Eruption of Riverside Geyser, Firehole River, Upper Geyser Basin, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Winter in Midway basin, buffalo beside Firehole river, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Buffalo beside Firehole River in winter in Midway geothermal basin, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America (U.S.A.), North America

Firehole River and Thermal Steam Yellowstone National Park WY

Bison Firehole River Yellowstone National Park WY

Tourists at Firehole River, Yellowstone National Park, Wyoming, USA

View over Firehole River, Geyser Hill, Upper Geyser Basin, geothermal springs in Yellowstone National Park, Wyoming, United States of America, USA

Runoff from Excelsior Geyser into Firehole River, Midway Geyser Basin, colored thermophilic bacteria, microorganisms, geysers, hot springs, Yellowstone National Park, Wyoming, United States of America, USA

Outlet of the Excelsior Geyser in Firehole River, Midway Geyser Basin, colourful thermophilic bacteria, microorganisms, geysers, hot springs, Yellowstone National Park, Wyoming, United States of America, USA

Steaming geothermal springs and geysers, Firehole River, Midway Geyser Basin, Yellowstone National Park, Wyoming, United States of America, USA

Colored thermophilic bacteria, outlet of the Cliff Geyser, Firehole River, Black Sand Basin, Upper Geyser Basin, Yellowstone National Park, Wyoming, United States of America, USA

Runoff from Excelsior Geyser into Firehole River, Midway Geyser Basin, colored thermophilic bacteria, microorganisms, geysers, hot springs, Yellowstone National Park, Wyoming, United States of America, USA

Firehole River in Yellowstone. Waterfalls of hot water.

Creek and pool in Biscuit Basin, Yellowstone National Park, Wyoming.

Sapphire Pool in Biscuit Basin, Yellowstone National Park, Wyoming.

Black Opal Pool in Biscuit Basin, Yellowstone National Park, Wyoming.

Sapphire Pool in Biscuit Basin, Yellowstone National Park, Wyoming.

Pair of American Bison bulls (Bison bison) walking through the 'Bobby Socks' trees in the Firehole River Valley of Yellowstone National Park; Wyoming, United States of America

American Bison bull (Bison bison) plowing through deep snow in the Firehole River Valley, Yellowstone National Park; Wyoming, United States of America