This massive railroad spike celebrates the 1939 premiere of the movie “Union Pacific.”

This Italianate Villa-style castle is pretty to look at, just keep off the private property.

This mansion was made famous by its colorful cast of owners and location along the Sante Fe Trail.

This otherworldly church spire reaches up toward the heavens.

A remarkably opulent mansion with a tragic history.

Stand at the point where the two mightiest rivers in the United States converge.

Rumored to be the famed pirate's lookout tower, this historic stone structure is now just watching for tourists.

Where Saint-Martin ends and Sint Maarten begins (or vice versa).

Commercial airplanes land mere feet over the heads of sunbathing beachgoers on this tiny island.

From this scenic rockface, you can still see the paths Western pioneers followed.

A perfect circle of 24 mysterious holes dates back to prehistoric times.

The world's first aircraft factory has been hiding inside an automobile plant for almost 80 years.

The childhood home of the Wright Brothers in Dayton.

This monument is dedicated to those lost on June 6, 1944, in the town with that day’s highest per-capita casualty rate.

The tallest waterfall in West Virginia.

One day a year it is legal to jump off of this astoundingly tall bridge that spans an Appalachian gorge.

A spiritual vortex among the red rocks in Sedona.

This sinkhole in the Arizona desert is filled with carbonated, arsenic-rich water

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

The world's only teal arches exist in a city that cares more about its aesthetic than an Instagram influencer.

A historic hydroelectric power plant serves as the unusual backdrop for a public park.

This small, unassuming street is now a canvas for color and creativity.

The first permanent memorial to a unique secret weapon of World War II.

Some of the tallest ancient American ruins continue to inspire awe and curiosity.