The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Beneath the southern end of the Golden Gate Bridge is the “Gibraltar of the West Coast,” a fort built to protect the San Francisco Bay from naval attack.

California's own medieval Italian castle, authentic down to the 300-year-old iron maiden in the dungeon.

The capital of the Cayman Islands is a center of offshore banking, but gets battered by blistering hurricanes.

The hall of fame for circus performers.

Forget Hollywood, one of the biggest stars in the world can be found in Roanoke, Virginia.

This Transylvania County city is home to a rare white squirrel population that is descended from an escaped carnival animal.

The record holder for the world’s largest peach.

The innocent intentions of this monument are somewhat lost in the sculpture's muscled imagery.

One of the most influential presidents in U.S. history wanted only this plain, elegant monument as his lasting memorial.

An overlooked memorial honoring the local Washington residents who died in World War I.

There’s a special club house at the top for the bell ringers.

Look closely and you’ll notice that the color changes a third of the way up the tower.

A little marble compass above George Washington's (empty) tomb in the Capitol marks where D.C.'s four quadrants intersect.

An atomic bomb-proof strongbox protects the U.S. Constitution from terrorists and thieves.

The walls of the iconic dome are hollow and have a secret stairway.

The unedited photograph called "Bliss" has graced the screens of over a billion computers.

America's post-nuclear-attack chambers of Congress.

Classy up your Big Mac with bow-tied servers and chandeliers at the world's fanciest McDonald's.

The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

Centuries-old hoofprints and wagon tracks reveal themselves after a good winter storm.

One of corporate America's best-kept secrets is also one of the most publicly displayed.

This abstract roadside poultry was saved from demolition by outraged drivers and pilots.