Three and a half miles of cliffs, rocky beaches, Gilded Age mansions and 40 Steps to nowhere in particular.

A winding, cliffside stretch of road overlooking the Delaware River.

Stroll through a wonderland of stupendous moss-covered trees.

The home where the famous astrologer wrote some of his most telling prophecies.

This historic stone gate tower is now just a lonely relic in the middle of a swamp.

Once in disrepair, this popular Texas stop along iconic Route 66 has been restored to its past glory.

This historic railroad hotel built from Kansas limestone was once the most popular hotels for traveling salesmen in the midwest.

This tiny cafe is one of the last meeting places of its kind, allowing revolutionaries a place to plot.

This massive blockhead sculpture hides an entire library.

This lesser-known Frank Gehry building houses a treasure trove of cinema history.

This Parisian fountain is a little bit fantasy and a little bit nightclub.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

What if all public housing projects had been designed by "the Pygmalion of modern architecture," not only their prototype?

The castle where the Marquis de Sade lived out his darkest fantasies.

Even France's favorite aquatic son Jacques Cousteau, couldn't get to the bottom of it.

The mental institution where Van Gogh created some of his most famous work now allows guests to walk in the artist's footsteps.

The world's tallest bridge is also possibly the most elegant.

An Orthodox church built by the Royal Family for the Russian community exiled to the French Riviera.

This Bordeaux parking garage has 712 indoor spaces, and one outdoor.

These tall, red sandstone pinnacles outside Moab are often forgotten amid their more famous neighbors.

One of the world’s largest collections of petroglyphs records 2,000 years of human activity.

A beautiful example of 18th-century engineering still standing tall.

If you look closely at the oldest bridge in Paris, you might notice hundreds of ugly faces leering from its sides.

Soaring over the Niagara Whirlpool since 1916.