At just six feet two inches deep, it is said by Guiness and Ripley to be the world’s narrowest freestanding office building.

The colorful, smiling concrete silos of Vancouver.

A working steam clock, one of only a few in the world, located in Vancouver's Victorian Gastown.

This is an amazing but little known tile mosaic mural that used to grace the lobby of an office building in 1958, but now can only be seen from the second floor of a Shoppers Drug Mart.

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

This large, circular tomb is the final resting place of the first emperor of Rome.

This hydrochronometer was invented by a Dominican monk and is a prime feature in this garden.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

This hidden Art Nouveau courtyard is an opulent feast for the eyes.

A forgotten "city of water" underneath the famous Trevi district.

This ferry carries passengers across the Rhine propelled by no engine or paddles but by the river's current.

Founded by members of the Tohono O’odham Nation, this one-room joint's James Beard–winning fry bread is light as a cloud.

The "Father of Arizona" tried to build a Zoroastrian fire temple on the hill where he's now buried.

At an isolated roadside rest area stands a monument marking where famous Western star Tom Mix died in 1940.

Some of the tallest ancient American ruins continue to inspire awe and curiosity.

A reproduction of earth's many biomes.

Rusting dinosaurs frolic at the entrance to this roadside "snake sanctuary."

The outcropping is graffitied with the name of the beloved musical Muppet television series.

At this research institute, the chile is king.

This site honors the end of a 100-year boundary dispute between the United States and Mexico—all started by a river's shifting course.

A Texas cave network is home to some of the world's most spectacular-looking and bizarrely named mineral formations.

A colorful public mural in San Antonio's West Side encourages students to stay in school.

The 40-foot-tall votive candle is the largest of its kind.