20 of the World's Most Beautiful Heritage Sites - #20

20. Yellow Stone National Park, USA

For sheer diversity, Yellowstone National Park has to be among the United States' best natural wonders. Contained within a 9,000-kilometer-squared chunk of Wyoming, the world's first national park contains half of the globe's known geothermal features, and is home to an equally impressive array of wildlife including grizzlies, wolves and bison.