No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

One of Mexico's youngest major cities still holds on to this structure representing its short modern history.

Located outside Medellín, this Colombian park focuses on conservation and sustainability.

A 10 million-ton rock once worshiped by the Tahamies Indians, accessed by an astounding staircase.

The Andean town where every single building is decorated with a brightly colored frieze.

Inside the cloister of the Temple of San Juan Bautista is a ceiling decorated with gold Baroque illustrations.

In Coyoacán, a pair of coyotes crown a public fountain in reference to the ancient Aztec name of the borough.

A Parisian exterminator's shop whose storefront displays stuffed rats hanging from traps.

Beggars were miraculously "cured" of their fake ailments when they returned home to this 17th century Paris slum each night.

If you look closely at the oldest bridge in Paris, you might notice hundreds of ugly faces leering from its sides.

A poem by Arthur Rimbaud is inscribed on the wall of a street that, while it is only one block long, plays a key role in multiple novels.

This 18th-century sundial was designed to calculate the date of Easter each year.

An unusual number plate signifies the building's saucy past.

An overlooked marble is the only surviving in-place 18th century example of the measurement that changed how we define distance.

19th century pendulum and a clock restored by a rogue group of guerilla artists.

Pitié-Salpêtrière was the dumping grounds for women who received the dreaded diagnosis of "hysterical."

Different sections of the Zemun Fortress were built in the 14th and 15th century as a response to the advance of the Ottoman Empire.

This statue of the famed author, actor, and journalist is made entirely of screw-nuts.

A surrealist timepiece by the artist of melting clocks.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

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

The tomb of history's greatest potato promoter is surrounded by tubers.

France's most famous cemetery, with some of its most curious tombs.

Explore the 500-year history of silk-making in Lyon at this museum, workshop, and boutique.