There aren't too many operational funiculars around, but Pittsburgh has two!

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

The United States’s oldest funicular railway glides up and down a steep Pittsburgh street.

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

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

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

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

The Byzantine, pre-Columbian, and medieval art at this stately mansion are some of the most under-appreciated collections in D.C.

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

A historic estate packed with George Washington's heirlooms, and its own nuclear bunker.

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

A tiny piece of the Moon is embedded in this stained glass masterpiece.

Home to items never before seen by the public.

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

The Corinthian columns that towered over Abraham Lincoln’s inauguration stand proud.

The Pentagon is so large that it was planned like a city, complete with internal highway infrastructure.