A snapshot of the city's fascinating voodoo culture.

The world's only international cryptozoology museum is host to an unrivaled collection of mysterious objects.

No one messes with the Massachusetts sacred cod, not this time...

The history of the tea trade is told in bas-relief on this historic pair of Boston doors.

One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.

A morbid secret lies hidden within the beautiful walls of the Boston Athenaeum.

This Boston medical museum features the skull of the famous medical case of Phineas Gage.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

Possibly the oldest church in Barcelona, this basilica has its pagan and Christian mythologies all mixed up.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

This cafe offers a curated collection of treats and tipples made by monks and nuns.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

Mountain where Jesus was first tempted by the Devil.

Barcelona's historic 19th-century sewers, whose foundations were laid in medieval times, are open to the public for exploring.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Shrapnel, dynamite, bullets and Franco couldn't destroy this bust, rescued and kept hidden as a family secret for over 40 years.

Among the oldest structures in Madrid, these Moorish walls once guarded the medieval city of Mayrit.

This macabre masterpiece of a mural is one of Francisco Goya's "Black Paintings."

The lengthy skeleton of one of the tallest Spaniards of all time is on display in Madrid.

Commonly acknowledged as the only public monument to the Devil himself.

Abandoned for decades, trains still pass through the now-restored remains of one of Madrid's first metro stations.

An ancient Egyptian temple in the middle of Madrid, Spain.