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.

The "lovely red Vega" of the legendary record-settling pilot.

The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.

Washington's iconic carousel has a nice piece of Civil Rights history.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

Four bald cypress trees in Lafayette Square, across from the White House, mark the southern edge of a 100,000 year old cypress swamp.

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

A clone of a cloned tree that was so important it allegedly had its own guards.

This restaurant has been a haven for D.C.'s LGBTQ community since the 1950s.

The most accurate timepiece in the world.

Decades before the scandal, this staircase on the river was a literal "water gate."

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

This lovely pocket park is one of the most under appreciated in D.C.

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

This stately mansion, built in 1787 by America's first Secretary of the Navy, is rumored to be one of the most haunted buildings in Washington, DC.

D.C.'s first central library was born out of a chance encounter with the philanthropist whose name it bears.

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

A haunting tribute to pioneering photographer Clover Adams.

The house where John Wilkes Booth conspired with his co-conspirators.

A super-sized promotional trick that is now a D.C. landmark.

Home to a vast and influential collection of Shakespeareana.

An obscure public service from the U.S. government that redeems burnt, moldy, and soiled old greenbacks.

The first purpose-built art gallery in the United States is once again open as a center of craft arts.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.