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

Near the former site of numerous witch burnings, this lavish Edinburgh mainstay pays homage to Scotland's brutal history.

"Respectful to the dead, safe and sanitary to the living, dedicated to the Genius of Memory..."

A strange rock with a sinister reputation lurks within the crimson waters of this Scottish glen.

A 30-acre garden inspired by the principles of modern physics.

The fountain marks the area where hundreds of accused witches were burned at the stake.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

A luxurious doomsday bunker hidden beneath an unassuming Las Vegas home offers the best of subterranean suburbia.

An exotic wildlife habitat right off The Strip.

Brightly colored 30-foot-tall totems light up the desert sky just outside Las Vegas.

Apartment complexes built into huge repurposed natural gas tanks.

The former private quarters and office of Dr. Sigmund Freud now hosts a museum housing the works of the founding father of psychoanalysis.

The bunker where Hitler took his own life is hidden under this deliberately ordinary parking lot.

There must be a pun in this haystack somewhere...

At this exhibit on the world of poison, venomous animals steal the show.

Residing along a busy thoroughfare, this sculpture urges passersby to consider the future.

A pair of giant stone heads represent the ancient Roman saints beheaded here.

A rare water-powered funicular, it uses a huge tank of water and gravity to do its work.

The many—66 to be exact—faces of the German forest.

Macabre museum devoted to historical Viennese murders.

A castle from the Holy Roman Empire that hosts traveling youth... in its stables.

This abandoned coliseum was intended to be a grand Nazi rallying ground before it was halted at the end of the war.

This historic toy museum brings a little whimsy to a city not usually remembered for such things.

This cubist Vienna church building looks like some sort of alien stonehenge.