One of the steepest streets in the United States makes an intriguing challenge for cyclists.

Mysterious rocks that ring musically when struck.

World's first "penitentiary," meant to be humane, drove men insane.

The site of a 19th century "dream city" that almost rivaled Chicago before being swallowed by the Indiana sand dunes.

There are eight natural springs around town, each with a slightly different taste.

This razorback ridgeline has doubled as a scenic drive since the early 1900s.

This super steep hike ascends 2,000 feet in less than a mile.

The highest bridge in America was built for an almost unnervingly small amount of money.

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

The current Eureka County Courthouse replaced an all-wooden structure that had previously been an ice-skating rink.

The unedited photograph called "Bliss" has graced the screens of over a billion computers.

One of the most scenic stretches of road in America winds between some of the country's oldest trees.

An emerald-green grotto just a short trip from Austin.

A popular swimming hole that hides one of America's most deadly diving spots.

In Paris, Texas, even Jesus wears cowboy boots.

In Paris, Texas they have their own Eiffel Tower, it just has a cowboy hat on it.

This opulent 16th-century Maharaja’s palace is a unique mix of Hindu and Muslim designs.

More than half of this Indian palace is drowned but it looks all the more spectacular for it.

The 953 windows undoubtedly make this the world's most beautiful screened porch.

Known as the leaning temple, the sacred structure has somehow developed a severe nine-degree slant.

The abandoned site of the Beatles spiritual awakening and subsequent revolt.

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

A hugely vast Irish landscape of barren rock that stretches for miles.

The walls of the iconic dome are hollow and have a secret stairway.