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Yellowstone National Park
/ˈjɛloʊˌstoʊn ˈnæʃənl ˈpɑːrk/
National park in the United States of America

Definition

Yellowstone National Park is a national park located in the U.S. states of Wyoming, Montana, and Idaho. It was established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872. Yellowstone was the first national park in the U.S. and is also widely held to be the first national park in the world.
http://www.nps.gov/yell/index.htm
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