Once forgotten and built over, this historic Black cemetery now houses a poignant memorial.

Railroad officials in the early 1900s sought to spare travelers the sight of Roman soldiers’ private parts.

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

A traveling postal dog covered 48 states and more than 140,000 miles, and he lives on as taxidermy, patched up with a rabbit's foot and a pig's ear.

An easily overlooked memorial to a Ukrainian famine-genocide that killed over 4 million people.

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

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

A three-story tower of books about Abraham Lincoln is one of the more unusual monuments to the president.

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

This statue of the "father of television" stands prominently in the United States Capitol.

Rumor has it the uncarved lump behind the three famous suffragists is reserved for the first woman president.

A heroic pigeon that, through a barrage of gunfire, delivered a message that saved over 100 lives in World War I.

This taxidermy horse was a Civil War hero.

Perhaps the most scandalous statue of America's first president.

The most decorated dog of World War I is preserved in the Smithsonian.

The story behind this beloved toy—named for Theodore Roosevelt and owned by his grandson—is more complicated than you might guess.

An overlooked tribute to one of the most important peace deals in American history.

The little-known, 300-year history of the area includes former lives as a bustling tobacco port, parking lot, and industrial dump.

The oldest building in the District of Columbia was preserved because of a mistaken connection to George Washington.

An obscure federal monument honors the French diplomat who served as Ambassador to the U.S. during WWI.

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.

A Civil War fort in the middle of Washington, D.C. has been swallowed by a forest.

The Pentagon sits on a former island that was in Virginia at low tide and D.C. at high tide.

The national park was once a plantation estate.