Press 1 for knock-knock jokes.

The innocent intentions of this monument are somewhat lost in the sculpture's muscled imagery.

An overlooked memorial honoring the local Washington residents who died in World War I.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

A much-maligned monument to teetotalism.

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

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

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

A nostalgic bibliographic gem.

The oldest continuously operating fish market in the United States.

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

During the Industrial Revolution this “Temple of Invention” was full of intricate miniature machines and gadgets.

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

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

A wondrous old library overlooking the nation's capital.

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

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

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.