One of Catholicism's four major basilicas has a series of papal portraits that are said to predict the end of the world.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

A curious carving hides on a marble column in the Mosque-Cathedral of Córdoba.

Once the grandest synagogue in medieval Spain, it now stands as a memorial of the 15th-century Jewish exile.

A display of torture devices used in the Spanish Inquisition and other scourges of medieval Europe.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

The palatial McDonald's that inspired Wesley Willis.

This historic house museum that celebrates one of the world's most influential social reformers is also one of the most haunted locations in Chicago.

Chicago was once a major hub of film production, but being silent film you don’t hear much about it.

This cheerfully-named branch of the Chicago River is the fetid result of years of blood, entrails, and meatpacking waste.

This memorial plaque remembers a strangely shallow maritime disaster known as "Chicago's Titanic."

Recognized the world over as the home of the McCallisters in the 1990 movie "Home Alone."

Each of these gorgeous, intricately decorated rooms is painstakingly crafted to the scale of 1 inch: 1 foot.

A science teacher's dream.

Eclectic collection of rare and beautiful stones in a historic home.

Partially submerged Buddha heads freckle Chicago’s neighborhoods.

An antiquated German apothecary on Chicago's North Side.

This restaurant proudly displays bread signed by the 39th president.

A new sculpture calls attention to climate change in the centuries-old city it threatens.

Two stone columns flank the grand Venice square, but there were supposed to be three.

The colonial city's social history is reflected in its fanciful door knockers.

A fantastical 13th-century fortification sandwiched by a modern hotel in central Brussels.

A little sculpture with a large wardrobe.

This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."