The best place to send your postcards home from Antarctica.

Admire a Lilliputian replica of the fast food outlet.

As if T-rex wasn't big enough, this Canadian monument is four times larger than the real thing.

Hoodoos, naturally eroded land formations, stand 20 feet tall in the Canadian badlands.

Not for the faint of heart, this long pedestrian bridge rewards those who brave the wobbly walk with a beautiful view.

This ghost-town bar has bullet holes and plenty of stories lurking within its walls.

To get to or from this Canadian ghost town, you'll need to cross 11 single-lane bridges.

The pretty iron lamp is a reminder of the architecture underneath London's streets.

This cannonball embedded in the side of an Edinburgh house once served a surprisingly pedestrian purpose.

The Hveragerði fissure runs through this unassuming shopping center.

An amazing example of early-20th-century architecture, this church features marble transported from Utah.

Behind an abandoned storefront is an example of pioneering 1930s gas station architecture.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

A tiny monument to the unsuccessful attempt by Thomas Jefferson to place the prime meridian in Washington.

Before Nixon, "watergate" meant canals.

Washington's top-secret Cold War-era doomsday communications tower is located in a small neighborhood park.

One of the largest artillery pieces in the world sits in a Washington D.C. parking lot.

Members of Congress have traveled between the buildings on Capitol Hill for a century hidden from tourists, press, and storm clouds.

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

Washington's iconic carousel has a nice piece of Civil Rights history.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

The span is crooked and made from two older recycled bridges.

A clone of a cloned tree that was so important it allegedly had its own guards.

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