With more than 10,000 geysers, hot springs, fumaroles, and mud pots, as well as cubic mile upon cubic mile of once-incendiary rhyolite, the landscape of Yellowstone Country vividly displays its fiery past and present. The region contains 1/5 of the world's geysers, including the most famous of them all, and is the setting of some of Earth's most destructive volcanic eruptions. The 19 road guides in Roadside Geology of Yellowstone Country fully explore this volcanic pedigree while also delivering you to sites that have recorded the region's broadand deep geologic story, which includes exquisitely preserved, 50-million-year-old petrified trees buried in conglomerate; mountain-sized blocks of rock that slid more than 50 miles in a massive debris avalanche; the glacially carved craggy peaks and U-shaped valleys of the Beartooth Mountains and Absaroka Range; and the Grand Canyon of the Yellowstone, the excavation of which is still a mystery.