Venice's "Island of the Mad."

This abandoned island off the Venetian coast has been a radical monastery, a political prison, and a secret Nazi base.

The Cathedral of St. Ambrose has been hiding a special parishioner within its walls.

This mummified mermaid corpse is an aquatic curio that was eventually revealed to be a fake.

One of the oldest and certainly best preserved Cistercian abbeys still in existence.

The ghosts of Britain's telecommunication past sit rusting away in a small village in England.

The gloomy ruins that inspired Bram Stoker to bring Dracula to life.

These 20-foot jaw bones honor a time when the leviathan bones were a sign that whalers survived the hunt.

The view that inspired the scenes of Dracula's first landing in England.

The curious and tiny collection contains some very odd objects.

A magnificent winding road through a steep valley, with deep natural caverns at the bottom

A metal tree emits eerie, melodic notes on top of Lancashire's Crown Point.

A stone obelisk towering over the surrounding countrysides beckons hikers across the rolling moors.

One of the largest mechanical models of the solar system in the world.

A giant wooden soda bottle pays homage to a distinctly British drink on the very spot where it was invented.

Hidden on the urban banks of a Manchester river are a series of abandoned waterside industrial sites.

Wedged between two buildings at the Great Ormond Street Hospital is this secret music installation.

A famous burial ground with a history both grim and literary.

The John Snow Memorial marks the epicenter of London's 1854 cholera epidemic.

This London plaque marks the spot where David Bowie's famous alien made his debut.

A collection of comics, graphic novels, animation and caricatures devoted to exploring this often overlooked art form.

The childhood home of Earth's alien chameleon is a humble Brixton flat.

The barrel-made lookout from Shackleton's final ship is tucked away in the crypt of one of London's oldest churches.

An abandoned tank sits in an empty London lot as a symbolic middle finger to local city planners.