An ancient burial ground believed to have been used for ritual sacrifice.

A 15th-century granary that played the role of futuristic slave quarters in the world of 'Star Wars.'

The best-preserved Roman small town in North Africa.

Art deco landmark on the outskirts of Washington, D.C.

Once the supplier for noteworthy projects like the National Cathedral, this old brickworks now lies abandoned.

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.

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

This Armenian monastery was carved out of cliffs and named after the spear used to stab Jesus.

The iconic D.C. restaurant where the Cuban Missile Crisis was negotiated, now a Walgreens.

One critic described it as "middle Mussolini, early Ramses, and late Neiman-Marcus." Another called it an architectural "natural disaster."

Washington's iconic carousel has a nice piece of Civil Rights history.

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

Perhaps the most scandalous statue of America's first president.

The national park was once a plantation estate.

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

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

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

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

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.

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

One of the dwarven trees dates back to 1625 and survived the Hiroshima bombing.

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

The United States Capitol's former columns still stand.