"De-Hazing the Lazy Days of Summer"
"It's high season in the nation's national parks as millions of visitors come to see nature. If last year's visitor figures hold up -- and early indications suggest they will -- nine million visitors will see the Great Smoky Mountains, the most visited national park. Three other parks -- Grand Canyon (more than four million visitors in 2011) Yellowstone (about three million) and Acadia (more than two million) -- combined will attract roughly the same number."