A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

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

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.

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

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

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

Where the U.S. government kept its actual treasure, before Fort Knox.

This 1,700-pound edible sculpture is way better than your average chocolate mousse.

Walk the same tracks that once ferried Gilded Age aristocrats to their vacation destinations.

The gravestones in this historic cemetery are carved with mysterious faces.

A strange, heartwarming, decades-old declaration of love on a New Hampshire roadside.

At 207 feet, one of the world's longest continuous escalators.

This bright yellow relic is the final survivor of a short burst of seashell-shaped petrol pumps.

More than a century after her death, Little Gracie Watson remains one of Savannah's most often-visited residents.

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

One of the longest water bridges in the world was built over a supposedly haunted swamp in Louisiana.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

The final resting place of the camel who served with the Confederate Army during the Civil War.

The Old Courthouse takes visitors on a captivating trip through St. Louis' timeline.

Speak to a companion on the other side of the room loud and clear through this architectural anomaly.

A historic house in St. Louis was plagued by a series of suicides committed by family members involved in a successful brewery.

A brick-paved former section of the historic coast-to-coast highway.

This erect, phallic geological spire wasn't always named so domestically.