One of the oldest reform schools in the United States, home to wayward boys such as Merle Haggard, now abandoned.

A fantastic castle rumored to be the birthplace of King Arthur.

A marvel of Byzantine engineering under the streets of Istanbul.

Extraordinary sculpture garden created by an eccentric English poet.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

These remote Florida islands have a history of sea turtles and sunken treasures, and one of the world's largest coastal brick fortresses.

Amazing and mysterious Neolithic settlement on Scotland's Orkney Islands.

Venice's "Island of the Mad."

The angel of death appears to weep black tears at this grave marker.

A speakeasy takes on Chicago's drinking culture.

A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.

A book collector's dream, this Toronto bookstore has the world's first "Biblio-Mat," a random book vending machine.

This floating cinema brings new meaning to the phrase "going out" to the movies.

Stalactites and stalagmites in a beautifully lit cave.

A beautiful geyser under environmental threat.

Possibly the most beautiful carillon in the world, set atop Iron Mountain in Florida.

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

Ruins of a German Castle on top of a towering stone pillar.

Hellam Township is reputed to feature seven remote gates, which when passed through in the right order, open an entrance to hell.

Crypt mausoleum in cathedral's basement contains relics of third century Roman martyr, Saint Vibiana.

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

These azure waters were thought to lead to the Mayan Underworld.

Famously misunderstood wonder of the ancient world

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.