A fantastic array of trays and cables once whisked books over to the Capitol at 600 feet per minute.

Senators used to relax in the nearly forgotten marble tubs now hidden in the U.S. Capitol Building's basement.

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

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

Members of Congress have traveled between the buildings on Capitol Hill for a century hidden from tourists, press, and storm clouds.

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

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

The privately owned cemetery that holds room for Washington's finest when they step down from life.

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

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

Sit where JFK proposed to Jackie or where Nixon dined on meatloaf at this storied pub.

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.

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

The most accurate timepiece in the world.

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

This imposing Masonic temple a mile from the White House was the first public library in Washington, D.C.

Largest Roman Catholic church in North America.

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

The national park was once a plantation estate.

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

The oldest continuously operating fish market in the United States.

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

The country's oldest continually-operated mini golf course lies hidden in plain sight, eclipsed by one of D.C.'s most popular tourist attractions.