Geysers in Yellowstone National Park

Riverside Geyser with a rainbow

Riverside Geyser is on the banks of the Firehole River and water from the eruptions lands in the river. On sunny days a rainbow is visible during the steam phase (towards the end of an eruption). There was a very strong rainbow for a large part of this eruption.
Date: August 25, 2010
Location: Upper Geyser Basin, Yellowstone National Park, WY