This surprising gem is a world-class archeological museum hidden at the University of Chicago.

At Chicago's revered Field Museum, visitors are invited to learn about and literally explore DNA.

The twin towers in this Chicago fountain use 50 foot tall video screens to spit on people.

This $3 million model train takes you through Chicago, Seattle, and the thousands of miles in between.

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

This historic hotel invented the chocolate brownie.

A gothic church spire sits atop this skyscraper, the tallest church in the world.

An antiquated German apothecary on Chicago's North Side.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

Hundreds of years ago, this lion-shaped door knocker could help a person accused of a crime find temporary safe haven in Durham Cathedral.

This cathedral's stained-glass patchwork of psychedelic colors and shapes was put in place long before the swinging 60s.

Only a few pieces remain of the structure that carried people and goods across the Thames for some 600 years.

Built 1,500 years ago, this abandoned Mesoamerican city is surrounded by a natural wall made of outstanding rock formations.

A hotel masquerading as a medieval castle overlooks a Mexican city.

This highly decorated dam is one of Guanajuato's most unexpectedly beautiful public works.

A Mexican Romeo-and-Juliet-esque legend has given this super-narrow alleyway a reputation for romance.

This landmark cemetery in Boston was created more than 300 years ago.

Beneath the impressive baroque cathedral that rises from the center of Berlin lies the largest collection of Prussian royals in the world.

The mummified right fist of a 1,000-year-old saint-king sits inside an ornate golden reliquary.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

A neo-Gothic temple in central Mexico featuring a labyrinthine network of crypts.

The preserved left hand of a saint once known as "the Pearl of York."