In the third edition of this classic work, T. Scott Bryan returns to the topic of the world's most dynamic geysers, updating readers on their shifting activity and distinct personalities. With a focus on the geysers at Yellowstone National Park including Old Faithful, Castle, Grand, Steamboat, and Echinus, learn why some geysers tease with gentle splashes, barely lifting water above their pools, while others thunder skyward in columns that soar hundreds of feet. Why do a few slumber for decades before surprising onlookers with sudden bursts, while others erupt with clockwork regularity, year in and year out? Using vivid, color photographs and clear, engaging language, Bryan unravels the mystery of geysers and geyser basins: why they appear in certain landscapes, how they form, and why some bubble while others steam or explode with spectacular force.