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

An abandoned NSA listening post on Berlin's "Devil's Mountain."

Started as a kitchen garden, now the second largest botanical garden in the world.

The bones of some 7,000 soldiers killed in the historic Battle of Solferino are stored here.

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

The tomb of one of Scotland's bloody historic villains is a magnet for bumbling desecrators.

A fernery hidden by neglect is uncovered, and an ancient specimen along with it.

This castle was established by the 4th Duke of Montrose and is connected to the Buchanan Clan.

Perfectly preserved ancient monastery in an impossibly dramatic location on a rocky island in the Atlantic.

An Irish cemetery filled with victims of political strife and violent conflict, including the grave of Bobby Sands.

The remains of 40,000 humans, meticulously stacked in a tiny churchyard shed.

This disused VLF radio station is no longer in service but the surrounding town still bears its name.

A former plague hospital turned medical museum.

Museum preserving torture methods from the past.

The giant scales in this museum can still tell if someone is one of the devil's brides just by weight.

A curious collection dedicated to human and animal anatomy and pathology.

A 18th century graveyard and its astonishing cortege of macabre iconography.

One of the oldest scientific gardens in Britain, containing more than 13,302 plant species in its core collection.

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

A historic arboretum and non-conformist, non-denominational park cemetery.

A vast overgrown cemetery, once known as one of London's "Magnificent Seven."

This historic "City of the Dead" lies prominently in the center of New Orleans' famous Garden District.

A museum devoted to bringing to light forgotten or neglected histories through exhibitions, education and public programming.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.