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

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

One of Jeff Koons’s largest sculptures and his first commemorative work.

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

The spiral staircase hidden inside this giant Parisian column was likely built for Catherine de Medici's astrologer.

One of Monterrey's oldest buildings is perched atop a hill boasting impressive views of the city.

A mysterious, ancient collection of pre-Hispanic petroglyphs hidden deep in the Mexican desert.

This ”skyspace,” which bears a resemblance to a spacecraft, is designed to disappear in the presence of light.

A mountaintop shrine named for the road to heaven.

After it was missing for a decade, this 40-foot statue of Our Lady of Guadalupe was found and returned to a place of honor—with a little help from a tropical storm.

A former travertine mine traces the geological history of this unique desert filled with crystalline blue pools.

A Beaux-Arts architectural surprise and a charming nostalgic tour through northern Mexico’s railway revolution.

A miniature beach in the middle of the desert.

A spectrum of colors awaits visitors to one of Mexico's most gorgeous bodies of water.

Swim alongside softshell turtles in these turquoise waters within the Cuatrociénegas Biosphere Reserve.

The majestic, sacred tree is represented on this piece of public infrastructure.

A honeycomb-like structure of interlocking shelves creates a beehive of books.

These gleaming gypsum sand dunes are the second-largest in North America.

A miniature Italianate fantasy village on the coast of Wales and the set of ITC classic "The Prisoner."

This southwestern historic site was designed and built by an artist who wanted his work to "feel at home."

Numberless clock creates a meal of time for the dreaded, insectile Chronophage.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

A labyrinthine underworld of tunnels and caverns hides beneath the city.

The stoic structure boasts a whimsical set of stained glass art commemorating Lewis Carroll.