This eccentric cave dwelling is bizarre even by the standards of a subterranean town.

Thousands of lawn gnomes have infested this Australian roundabout.

Is there such thing as too many fruit bats? Not anymore.

This trio of Australian rock spires may have inspired aboriginal legend or just modern tourism.

You'll find the little birds tucked within the rocks of this Australian beach.

One of the best beaches in the entire world.

The unique ecosystem atop an Australian mountain is home to some colorful inhabitants.

The labyrinthine storm tunnels beneath the city of Melbourne are ruled by a band of urban explorers.

A collection of outdoor mystical statues paying homage to indigenous Australians and ecological stewardship.

A castle hand-built by a Spanish dreamer in the Australian tropical jungle.

An abandoned railroad tunnel is now filled with bioluminescent bugs.

An Australian lake whose pink hue defies scientific explanation.

The United States Capitol's former columns still stand.

In the basement of the U.S. Capitol Building is a hidden storage room full of ornate floor tiles leftover from the 1850s.

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

The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.

The privately owned cemetery that holds room for Washington's finest when they step down from life.

This lovely pocket park is one of the most under appreciated in D.C.

Rumor has it the uncarved lump behind the three famous suffragists is reserved for the first woman president.

Perhaps the most scandalous statue of America's first president.

A hoard of sky catalogs, astrophysical journals, even the works of Galileo and Copernicus.

The hidden offices underneath Memorial Bridge have been locked up since 1976.

The first purpose-built art gallery in the United States is once again open as a center of craft arts.

There's a crumbling old mansion inside the Smithsonian National Zoo.