The second tallest railway trestle bridge in America.

A waterfall 600 ft. inside a mountain, once the bane of gold miners, is now a spectacle of nature.

A Hawaiian stairway to heaven—that you can't climb.

The White House Situation Room was taken apart in 2006 and shipped to the Ronald Reagan Presidential Library.

The unusual patterns in this rock formation result from two distinct modes of weathering.

Local lore holds that Butch Cassidy took an escape route through Red Canyon's sandstone hoodoos after an attempted murder.

So many migrating birds roost on the bridge, it has a special summer speed limit.

Erosion and various mineral deposits give this striking canyon its distinct color and soft appearance.

A rare tour of a commercial jet assembly plant, held inside one of the largest buildings in the world.

A dramatically eroding canyon thousands of miles from the desert.

The largest copper mine in Arizona, this enormous open pit emerges from the hills like an alien landscape.

This unusual lava tube spouts seawater during high surf.

The tallest The Church of Jesus Christ of Latter-day Saints temple in the world soars above the Beltway.

At the base of Steens Mountain resides an otherworldly desert.

A massive hydrovolcanic explosion left a half-mile wide crater in Death Valley.

A cooled lava flow from the Haleakalā volcano formed these surreal-looking columnar basalt structures.

"Where the ducks walk on fish."

Pulled from the rubble of one of the worst modern tragedies, a steel crossbeam became a symbol of hope for New Yorkers.

A remote desert lookout offers unparalleled views of the California badlands for those who brave the trek.

A historic and oft-filmed prison stands in a Chicago suburb.

A stunning landscape of bunkers that once stored chemical weapons.

At this deceptively beautiful beach, nothing is what it seems.

A dazzling display of red rocks weathered into spires and hoodoos.

Since World War II people have been decorating this stretch of the Yuma desert with signatures arranged out of rocks.