The elevator that makes it possible to fly American flags in bulk over the U.S. Capitol

In the basement of the U.S. Capitol Building is a hidden storage room full of ornate floor tiles leftover from the 1850s.

"Congress may voluntarily remain in session throughout the summer, in order that our Congressmen may be protected from the intolerable discomforts and dangers of the ordinary outdoor weather!”

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.

Atop this media building, two hives containing more than 30,000 bees keep the surrounding area vibrant.

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

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

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

The first memorial dedicated solely to the Black troops who fought for the Union.

Through the decades, Black music stars have performed at this historic hub for music and the arts.

The district's only illusionarium supports free writing programs for local students with every purchase.

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

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

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

A replica of the famous memorial statue at the Normandy American Cemetery hides in an office building in downtown D.C.

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

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

A gorgeous mural outside a beloved D.C. restaurant pays homage to famous Black Americans.

When it opened during the final years of the embargo, all the drinks and cigars were free.

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

The first presidential bomb shelter was located in an old vault under the Treasury, connected to the White House via tunnel.

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

There's an old indoor swimming pool hidden directly underneath the White House Press Briefing Room.

Disks are rolled out onto the south lawn to absorb the impact of Marine One's wheels like giant coffee coasters.