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.

The most accurate timepiece in the world.

A much-maligned monument to teetotalism.

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

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

Fittingly, America's museum of architecture is itself a magnificently designed old building.

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

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

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 beloved statue at the National Academy of Sciences is oh so inviting to sit on.

The walls of the iconic dome are hollow and have a secret stairway.

This leafy estate is worth $18 million and is so grand it has two mailing addresses.

Largest Roman Catholic church in North America.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

This grand gothic brewery has been pumping out suds for over a hundred years.

Home to items never before seen by the public.

The site of the climactic scene from the classic horror film is now a historic landmark.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

The United States Capitol's former columns still stand.

Once known as the Illinois Asylum for the Incurable Insane.