One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

Some 80,000 Delft Blue tiles line the inside of this Amsterdam walkway.

Amsterdam's narrowest house facade is a monument to 17th-century tax evasion.

Famed for its pie, this eatery has a hidden tunnel that allowed Catholics to secretly walk to church during the Reformation.

Elaborate tile work in this railway station tells the story of Portugal.

This restored Portuguese cafe may well be the most beautiful place in the world to grab a Big Mac.

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

Twelve natural mummies are displayed in the crypt of this former monastery school.

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

The scene of a legendary hunt is displayed on this building's facade.

The first public library in the Americas has more than 45,000 books dating back to the 15th century.

The splendor of this 17th century golden chapel has led it to be called the "eighth wonder of the world."

A 500-year-old series of tunnels long believed to be folkloric was uncovered beneath the streets of Puebla.

66,000 pieces of art, donated by one of the world's richest men.

The collection of intricate sculptures includes one carved from a mammoth's tusk

Part bookstore, part café, and part forest.

This massive Brazilian church is built like an angular, technicolor pyramid left by Mayans from the future.

Beautiful public park off the beaten path and away from tourists.

The largest library in Latin America owes its existence to an Old World earthquake and a Napoleonic invasion.

Eduardo Kobra’s breathtaking 32,300-square-foot graffiti wall took over Rio’s Olympic Boulevard.

This stunning Brazilian library contains the largest collection of Portuguese texts outside of Portugal itself.

An unlikely neo-Gothic castle in the Paraguayan countryside.

These abandoned Cold War-era bunkers are now a designated refuge for endangered bat species.

A brush maker used his factory to protect blind Jews from the Gestapo.