A recreated Stonehenge stands in a country field, complete with Easter Island moai heads standing as sentries.

A collection of massive stacked rocks in Texas includes a snarky note on the benefits of modern technology.

Alabama has a fiberglass Stonehenge. With apologies to Spinal Tap, this one is full-size.

Hidden in the hills of Western Pennsylvania lies one of the best-kept ghost towns in America that you can legally visit.

The Cold War-era "underground Pentagon" is a sprawling subterranean hideaway for the Defense Department.

This large garden vase urn has nothing to do with the seventh U.S. President—it was designed by one landscape designer to honor another landscape designer's contributions to the National Mall.

This Masonic lodge was the first major private building to be constructed in Washington, D.C. after the Civil War.

Dedicated to the man who created the first radio wave communication system.

Beneath unsuspecting visitors feet, a capsule containing pieces of America’s civil rights history.

This small hilltop church weaves the urban history of Washington, D.C. with the national history of the United States.

Press 1 for knock-knock jokes.

A memorial to a shareholder activist feared by CEOs around the United States.

A replica of the famous memorial statue at the Normandy American Cemetery hides in an office building in downtown D.C.

A tribute to the pop culture icon overlooks this Washington D.C. intersection.

A hidden passageway now marks the site of an assassination attempt on Ronald Reagan that some say broke a 140-year-old curse.

A small token of gratitude from freezing cold journalists who were given a warm haven while covering JFK's inauguration.

Where you can hail your favorite fictional commanders-in-chief.

Also known as the Founding Church of Scientology.

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

The only National Monument ever to go missing for nearly 50 years then resurface in a dump.

The first memorial dedicated solely to the Black troops who fought for the Union.

A bas relief commemorates the "Nuns of the Battlefield" who cared for soldiers on both sides of the conflict.

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

When it comes to handsignals (and colonialism) rock always beats scissors.