Late afternoon sun illuminates a red rock mesa with a dusting of snow.

The mighty trunks of giant sequoia trees

Two trees ? or one tree with two branches ? have been locked together for centuries.

El Capitan rising above a Yosemite meadow.

Montezuma's Castle cliff dwellings

Montezuma's Castle cliff dwellings

Saguaro cactus in the Gates Pass area of Arizona

Red sandstone and white snow dusting pinion pines with a high mountain looming over all through low-lying clouds.

Desert colors of red and yellow sandstone, pines, and snow in Oak Creek Canyon.

A castle-like rock structure silhouetted in the sunset

A majestic scene of sandstone mountains dusted with snow and valley oaks and pinion pines

A pool of water, a remnant of the last rains, in a dry wash in Tonto National Forest.

A stunning view of desert foliage in the forest with canyonlands stretching into the distance.

Sandstone cliffs, perhaps a lost mine on the cliff high above, and desert foliage in the canyon bottoms.

A magnificent waterfall dropping over shale cliffs into a circular pool below

Bubbling, babbling waterfall dropping over shale formations which have eroded in stepping-stone fashion.

Bubbling, babbling waterfall dropping over shale formations which have eroded in stepping-stone fashion.

Stream, waterfall, pools, and lush green foliage at Watkins Glen State Park.

Stream, waterfall, pools, and lush green foliage at Watkins Glen State Park.

Babbling stream flowing into a bowl-like pool at Watkins Glen State Park.

Stream following a steep and narrow canyon at Watkins Glen State Park.

Liberty Bell at Independence National Historic Park.

Liberty Bell at Independence National Historic Park.

The clocktower at Independence Hall

The clocktower at Independence Hall

The clocktower at Independence Hall

Plaque commemorating Benjamin Franklin at cemetery at Independence National Historic Park. "He tore from the skies the lightning and from tyrants the sceptre."

Chronology of Benjamin Franklin at cemetery at Independence National Historic Park.

Gravestone of Benjamin and Deborah Franklin at cemetery at Independence National Historic Park. "A penny saved is a penny earned."

Statue of George Gordon Meade, the victorious general at the Battle of Gettysburg.

Plaque detailing the career of General George Gordon Meade, the victorious general at Gettysburg. Besides the information on this plaque, Meade had served from 1851 to 1857 on the Lighthouse Board and had charge of building Carysfort Reef Light and Barnegat Light. From 1857 to August 1861, he had charge of the United States Lake Survey, now absorbed into NOAA.

The Gettysburg Address, on a plaque on the battlefield at Gettysburg.

Sea stacks, surf, and sun. Ripples and reflections in the late afternoon. The remnants of a continent march into the sea.

The road to Zion National Park

A view in Zion National Park

A view in Zion National Park

A view in Zion National Park

A view in Zion National Park

A view in Zion National Park

Goblin Valley State Park. Wind and water eroded features.

Goblin Valley State Park. Wind and water eroded features.

Goblin Valley State Park. The Goblins are much larger than they appear in images amer0040, 0041, and 0043. Wind and water eroded features.

Goblin Valley State Park. Wind and water eroded features.

Bryce Canyon National Park

Bryce Canyon National Park

Bridge over the Colorado River

Erosion of red sandstone

The Colorado River flowing through the arid southwest.

A natural bridge formation generated by wind and water erosion.