Watch This: America's Best Idea

Stranger than fiction: As late as 1870, few non-Indians had entered the land near the headwaters of the Yellowstone River, where legend had it you could shout into a canyon at bedtime and be awakened by the echo in the morning. When the members of one expedition wrote about their journey to the so-called Valley of Death, with its boiling sulfur springs and burbling mud pots, no publishers would bite. "Thank you, but we do not print fiction," one editor replied.

The 14,000-foot rest cure: For most people, getting over a bad cough means couch time and a steady drip of Ricola and Turner Classic Movies. For Sierra Club founder John Muir, curative R&R meant rugged camping in Washington State, where he scaled Mount Rainier. "Did not mean to climb it," Muir wrote to his wife, "but got excited, and soon was on top." The therapeutic outing, he added, left him with "heart and limb exultant and free."

Inquiring minds: "Park rangers have collections of stupid questions, because we so enjoy them," says former ranger Nevada Barr, whose favorites include "What time do the moose come out for pictures?" and the Zen-like "How much does this cave weigh?" National Parks writer Dayton Duncan has a soft spot for "Why did the Indians build their ruins so close to the road?

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