"On June 6, 1912, a new volcano emerged on the Katmai landscape and forever altered this region. For 60 hours, a volcano later named Novarupta sent ash into the sky as high as 20 miles (30 km). Ash and pumice from the eruption also rushed down the Ukak River valley as pyroclastic flows and surges moving at more than 100 miles per hour (160 kilometers per hour). The Ukak River valley was transformed into 40 square miles (64 square kilometers) of barren ash. Heat trapped in the ash took decades to cool. Any water buried by the ash or that percolated into it flashed into steam. The vents where the superheated steam emerged became the fumaroles that inspired the name Valley of Ten Thousand Smokes. Today the Valley of Ten Thousand Smokes (i.e. the Valley) offers a chance to explore a landscape created by the largest volcanic eruption of the 20th century. The beauty, scale, wildness, and mystery of the Valley make it one of the best places in the world to study the violence of volcanic eruptions and experience the raw power of nature."