A rather vulgar example of the transition from Latin to the Italian vernacular.

A fire once nearly devoured this gorgeous 14th-century Gothic cathedral.

When ecosystems collide in the arid Southwest.

The high point on the 16th president's eponymous roadway is marked by a massive version of his head.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

The Denver airport is guarded by a 32-foot-tall sculpture of a demonic horse.

Paranormal experiences in this hotel's room 217 led Stephen King to write "The Shining."

A downtown park built on top of unclaimed graves.

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

This tea house was a hand-built gift from Boulder's sister city in Tajikstan.

Washington's iconic carousel has a nice piece of Civil Rights history.

They sort through millions of dollars worth of diplomatic gifts on behalf of the government.

One critic described it as "middle Mussolini, early Ramses, and late Neiman-Marcus." Another called it an architectural "natural disaster."

The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

Home to items never before seen by the public.

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

The yawning maw of this pagan visage is said to bite off the hands of liars.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

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

The final resting place of the great navigator, or maybe his brother.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

When you've got to go, you've got to go.