At this airport "microcinema," you can catch a film before you catch a flight.

The only Leonardo Da Vinci painting in the Western Hemisphere.

The home and studio of one of the most celebrated female artists of the 19th century.

This funerary monument to the guillotined king and queen of France became a political lightning rod and a site of pilgrimage for French monarchists.

A wall of chewing gum moonlights as collective art.

In Egypt's expanding metro area, many of the neighbors are dead.

The only Roman honorific column in Istanbul.

This well-preserved Ottoman-era Cairene mansion hosts a facinating archive of Egyptian architecure, from the pharaohs and sultans to the modern day.

A grotesque Fiji merman dwells within this traditional Dutch-style building.

A circus legend leaves an unexpected endowment.

The largest stretch of the Berlin Wall is right on top of the former SS headquarters

Cages that once displayed the bodies of executed leaders hang from a German church tower.

Check the time in 145 countries at once with this East German relic.

This futuristic German television spire is actually the world's largest digital clock.

Twisted buildings adorn the banks of the Rhine river.

The world's largest kaleidoscope, designed by a 1960s psychedelic artist.

This outdoor gallery of sculptures along the East River was once a landfill.

This fancifully decorated Victorian home in New York’s Hudson Valley is the only known fully domed octagonal residence in the United States.

An institution dedicated to the towering buildings that make up skylines in New York City and around the world.

100 massive sculptures in the Hudson River Valley.

Dedicated to the art and science of glass in equal measure, this space is as much laboratory as museum.

One man's swirling six-acre monument of stone.

This futuristic airport terminal was abandoned for decades before reopening as a hotel—with a vintage plane of its own parked out back.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.