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

Look closely and you’ll notice that the color changes a third of the way up the tower.

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

An overlooked oasis of quiet on the grounds of Washington's monumental basilica.

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

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

There’s a hidden military meme engraved on the World War II Memorial.

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

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

The winding route passes through an enclosed alleyway, two tunnels, and leads to the White House basement.

A painfully obvious spy house sits right across the street from the Russian Embassy.

There's a 12-foot-tall replica of the Washington Monument hidden under a manhole nearby.

Possibly the most beautiful carillon in the world, set atop Iron Mountain in Florida.

A haunted hill that supposedly defied gravity.

Many of the murals covering this sleepy Florida town hide some sort of intentional error.

The graves in Florida's oldest Black cemeteries are marked with shells, stones, and mementos of the deceased.

Bronze footprints mark the path where a civil rights leader tried to march in peaceful protest before being knocked unconscious.

Intertwined, interspecies trees which locals believe can grant boons to lovers.

It's a pretty creepy lock-up.

A luxurious 1880s hotel with its fair share of Tiffany stained glass, Edison electricity, and of course, ghosts.

Arrr! The most authentic collection of pirate artifacts in the world... matey.

This monument honors the band's impromptu performance at Cadillac highschool's homecoming decades ago.

A collection of more than 10,000 racist objects that teaches the atrocities of social injustice and intolerance in American history.

Its floors are marked by colorful cues depicting Michigan's native fauna.