2300-year-old Roman road connecting the empire.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

This bridge was constructed from the rubble of the infamous Bastille.

This life-size replica of the Statue of Liberty's flame is also a tribute to Princess Diana by default.

Natural history museum celebrating biodiversity with a parade of taxidermy animals.

This statue was given to France by the United States to commemorate the centennial of the French Revolution.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

A mysterious shape catches the eye in this 16th-century painting.

Graffiti from the 16th and 17th centuries cover the walls of this part of the Tower of London.

An architectural oddity hides in plain sight on this iconic London bridge.

London's amazing modernist public square that never was.

A unique tribute to the millions of animals who served and died for the British military.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

Giant, friendly pelicans in Central London, the most unlikely of places.

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

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

"Congress may voluntarily remain in session throughout the summer, in order that our Congressmen may be protected from the intolerable discomforts and dangers of the ordinary outdoor weather!”

One day a year it is legal to jump off of this astoundingly tall bridge that spans an Appalachian gorge.

A 19th-century architectural wonder designed by the "father of the skyscraper."

The home of the first American-born saint is one of the only curved buildings in New York.

On the Hudson resides one of the largest clocks in the world.

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

This unique crypt designed by Frank Lloyd Wright for his longtime friend was not completed in either man's lifetime.