City law dictates that this mountaintop cathedral containing the heart of a saint is to remain the tallest building in town.

A grand Gothic Revival basilica with stained glass depictions of Montreal's religious history has only one soul resting in its crypt.

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

Outdoor escalators and art have helped change what was once a notoriously dangerous part of Medellín.

This Bogotá museum houses the world's largest collection of pre-Columbian gold relics.

Cathedral carved out of salt, located a mile below the earth's surface.

A 10 million-ton rock once worshiped by the Tahamies Indians, accessed by an astounding staircase.

A cozy bookstore and coffee shop in the heart of Cartagena's Old City.

The caldera of this mini-volcano has been turned into a naturally heated mud bath.

The Andean town where every single building is decorated with a brightly colored frieze.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

A historic observatory precariously perched at the "Top of Europe."

Avoid gangster interaction while window-shopping.

A bit of retro transportation flair preserved in the world's largest department store.

The "Seinfeld" diner.

This beloved Baltimore spot features caged dolls, a giant Pez collection, and many, many mannequins.

A startling, centuries-old subterranean marvel hides in plain sight.

It took 82 years and four different plaques to finally get the story right.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

A theme park featuring a replica of Noah's Ark built to the measurements specified in the Bible.

Cleveland's giant "free" stamp is a nod to the Civil War, but was misinterpreted for years.

An office built to look like a giant basket.

The home made famous by the 1983 holiday classic is now a perfectly preserved shrine to the movie.

Giant acorn-shaped 19th century gazebo from which suburban Washingtonians gazed upon the original "silver" spring.