Yosemite, California

In a high-country meadow two hikers crouch near the edge of a mirroring lake and watch a pika as it harvests blades of grass for a nest deep within a huge rock pile. When they resume walking, there is no other person in sight for as far as they can see. And on this sparkling summer's day, the view seems endless.

In the valley's crowded mall, families stroll by, eating ice cream, dodging bicycles. People pile in and out of buses. Shoppers hunt for souvenirs. Kids hang around a pizza place. Rock climbers, coils of rope slung over their shoulders, swap stories over beer on a patio. On a summer's day about 14,000 people are in Yosemite Village.

Both the solitude of the alpine ridge and the throngs of the valley are part of the experience when you visit Yosemite National Park. "No temple made with human hands can compare with Yosemite," wrote John Muir, whose crusading led to the creation of the park. To this temple come 3.3 million visitors annually. And about 90 percent of them go to the valley, a mile-wide (1.6 kilometer-wide), 7-mile-long (11-kilometer-long) canyon cut by a river, then widened and deepened by glacial action. Walled by massive domes and soaring pinnacles, it covers about one percent of the park. In summer, the concentration of autos brings traffic jams and air pollution.

Towering more than 350 stories above Yosemite Valley, El Capitan is the largest exposed granite monolith in the world.

The park’s giant sequoia trees can live to be more than 3,000 years old.

Yosemite Falls usually stops flowing in late August. The cascade is fed solely by snowmelt, so the peak flow is in late May, when high snows in the Sierra Nevada melt. Over the warm summer months the flow dries up—but returns around October, when snow again begins to fall.