The spur that wouldn’t die.

This lonely waterfront memorial to the men of the Titanic was erected by the "Women of America."

A tiny piece of the Moon is embedded in this stained glass masterpiece.

Part of a WWII submarine is lurking outside the Washington Navy Yard parking lot.

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

The institution is sitting on a goldmine of 21,000 paints, varnishes, pigments, and primers preserved for posterity.

The tunnel under the Capitol Building where Congress takes out its trash.

An unassuming, powerful monument north of the U.S. Capitol bears witness to the resilience of Japanese Americans during a time of grave injustice.

A secret greenspace hides atop a Capitol parking garage.

A Maryland museum dedicated to Black history, housed in a historic church.

This fort down the Potomac from Washington, D.C. was once the only defensive fort protecting the capital.

The stone marker that Mason and Dixon placed at the eastern end of the famous north-south border they surveyed.

This once-palatial plantation may have been the site where a draft of the Declaration of Independence was written.

A 300-yard long natural tunnel runs through a ridge deep in the Appalachian Mountains.

Giant busts of 42 U.S. presidents are sitting in a field in Virginia.

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

A memorial to the 1913 tragedy that helped protect the workers of the future.

This free, take-a-book shop seems like a trick but isn't.

These old doors are covered in the signatures of Rehoboth Beach artists dating back to the 1930s.

This historic iron-working village is now a ghost town so immaculate that it looks as though it was recently built.

The remnants of a wooden-hulled fleet built and abandoned in WWI, now home to a thriving ecosystem.

After hundreds of years of settlement, this once-bustling fishing village sunk into the Chesapeake Bay.

Housing the National Women's Party since 1929, this historic house is now a monument to the fight for gender equality.

Government testing at the asylum briefly explored using marijuana as a "truth serum" on Nazi prisoners of war.