The people murdered during a 17th-century Norwegian witch hunt have been honored with a pair of stark, modern installations.

Virgil's many-mouthed gateway to the underworld.

A submerged archeological park still holds the wonders of a Roman Sodom.

The deepest hole drilled in the name of science, where evidence of Precambrian life was found.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

A breathtaking array of ancient Pueblo structures and artifacts counterintuitively preserved by neglect.

Legends surround this jagged rock formation in the New Mexico desert.

The mysterious round rocks of Schooner Gulch.

This 29-ton granite ball spins around at the slightest touch thanks to a scientific phenomenon.

An acoustic anomaly with a mysterious cause.

An annual extravaganza of Broadway theater memorabilia.

The subterranean "lake" below the Paris opera house inspired the Phantom of the Opera's lair.

A once-booming Mississippi River town with a history of racial violence is now eerie and mostly abandoned.

This former coal gasification plant found a curious second life as a popular public park.

Remnants of cells from the most notorious London prison may lie in the basement of a rare Victorian Gin Palace.

An unlikely Transcendental Meditation haven in the American Heartland built around the ancient Vedic principles of balance and harmony.

The top of society once luxuriated in this world-class hotel, which continues to impress, even in ruin.

The medieval castle built as headquarters for the Pope's secretive Knights Templar.

Bubbling up from deep underground is the warm crystal clear water that fills the Warm Springs Pools, America's oldest spa.

The world's largest and most outstanding marl lake regularly changes color.

The ruins of the suspension bridge hang over Kingsbury Run as a ghost of racial prejudice.

There's a 12-foot-tall replica of the Washington Monument hidden under a manhole nearby.

With over 340,000 artifacts and counting, there is something for everyone, often called the "Smithsonian of the West."

A unique solar-powered pottery studio and gallery in the desert.