Top 10 Things You Didn't Know About National Parks

The Big One
Wrangell-St. Elias National Park and Preserve in Alaska is the largest park in the country. At six times the size of Yellowstone, it is the meeting point of four major mountain ranges and includes nine of the 16 highest peaks in the U.S. The preserve contains three climate zones, which means that it has everything from giant glaciers to wetlands to one of the largest active volcanoes in North America — in the Wrangell Mountain range, pictured here.

• Ken Burns, American Filmmaker