Terrifically morbid cemetary and site of famous Paracelsus' grave.

A tree planted by Marie Curie is treasured by the Radium institute that she set up.

An Inca spa, military outpost or maybe… both?

A plaque marks the spot where the saint was shoved off the Charles Bridge and into the river.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

This abandoned factory on the Hudson River once churned out a million bricks a week.

The remains of what was once the world's steepest passenger funicular.

This Central New York ghost town was once a prosperous railroad community.

Although it appears ancient and mysterious, the quirky folly was actually built 200 years ago by an eccentric estate owner.

Famously misunderstood wonder of the ancient world

A wooden statue of an Estonian pagan god and King of the Setos stands atop a sacred hill.

An illuminated manuscript comprising the life's work of a lone monk, inexplicably decorated with a portrait of Satan himself.

Town of spiritualists and mediums in Florida.

This little Vancouver shack is a temple to all things Hendrix.

One of the famous Czech artist's lesser-known Prague installations appears to be a glowing fetus affixed to a drainpipe.

These numerous Israeli caves were dug out over hundreds years for reasons ranging from hideouts to burial sites.

This daunting 1st century fortress was purportedly the site of one of the most dramatic revolts of the Jewish-Roman wars.

This historic rec center in the heart of Israel is a bastion of peace and togetherness.

Neighborhood in Jerusalem is home to the ultra-orthodox haredim.

Descend 2,030 years into the past in an ancient tunnel built to support Jerusalem's most famous wall.

A "gravitational anomaly" located in the redwood forests just outside of Santa Cruz, California.

This poignant sculpture of a gnarled weapon is a symbol of non-violence.

Never actually a tree at all, this spot was the site of London's public hangings for nearly 600 years.

This grubby wall is said to be one of the Earth's esoteric energy centers.