Every color in the rainbow awaits.

This hulking behemoth is actually five interconnected towers built in the 1960s.

The burial place of some of Mexico's most prominent residents is full of macabre stories and hidden masonic symbols.

Where layer cakes tower above one’s head and there is never a shortage of icing.

A museum in the former home of Marxist revolutionary Leon Trotsky.

The only castle in North America to ever house European sovereigns.

The famous artist couple lived and worked here, in two different houses separated by a bridge.

A church dedicated to the Mexican skeleton saint.

A jaw-dropping "megalibrary" that turns book-browsing into a geometric adventure.

Superstitious? Discover the witchy side of Mexico through its largest esoteric market.

Frida Kahlo's childhood home, now a museum of her life and works.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

A Victorian Gothic masterpiece housing a world-class collection of rare books and manuscripts.

Have a seat with the father of modern computing at this Manchester monument.

Dating back almost 400 years, the oldest public collection library in the United Kingdom was once the study hall of Karl Marx.

19th century museum with an eclectic mix of curiosities, from Egyptian artifacts to items on archery history to the skull of the world's oldest horse.

A scattered trail of street art adds a pop of color to the city's stark structures.

Glasgow’s piece of the patron saint of love.

A historic presidential getaway on the continental United States' southernmost island.

The island residents are known for taking their quirky sense of humor with them to the grave.