D.C. once had its own tiny rival to the New York Stock Exchange.

This fertility idol of questionable authenticity inspired an iconic Indiana Jones artifact.

The Byzantine, pre-Columbian, and medieval art at this stately mansion are some of the most under-appreciated collections in D.C.

This unassuming passageway played a key role in one of the most important events in U.S. history.

The house where John Wilkes Booth conspired with his co-conspirators.

Go take a picture with the inventor of the daguerreotype photographic process.

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

An echo chamber with a waterfall wrapped around its base at the Embassy of Canada in Washington, D.C.

A muscular Art Deco monument represents the struggle between regulators and unbridled markets.

A spectacular tribute to statesman and philanthropist Andrew Mellon.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

This mysterious structure by the Washington Monument is a flood barrier designed to protect the White House against rising waters.

A museum cafe showcases Native American dishes and indigenous ingredients from across the Western Hemisphere.

The remains of a historic plantation nestled in between a parking lot and the rental car return at Reagan National Airport.

Remarkably realistic Florida shoal bass "swim" inside this large globoid sculpture.

A Florida college boasts the world's largest single-site collection of structures designed by Frank Lloyd Wright.

There is an unmarked red button hidden over Houston's Buffalo Bayou that is just begging to pushed...

The famous animator's private station house and man-cave was the birthplace of imagineering.

High on a hill overlooking Los Angeles lives a world famous, high power conical Tesla Coil.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

Anza led the first Spanish settlers from Mexico to Monterey, California in the 1770s.

Murder, searching for gold, and being cut in half—the memorial statue of Daniel O. McCarthy and the Pioneers of '49

Scores of vintage street lamps shine along L.A.’s Miracle Mile.

These delicate buggers are some of the rarest fossils that have bubbled up from the Tar Pits.