Underneath this Byzantinian church lies a necropolis filled with ancient tombs and the ruins of previous churches.

A striking symbol of the Bulgarian capital.

A charming 17th-century alley is lined with secondhand bookstores and antiquarian shops.

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

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

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

This 1920s Dutch barge is now a floating bookstore.

Home to 10,000 medical specimens including the remains of Rudolf Virchow's extensive collection of pathological specimens.

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

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

Hungarian mummies in beautiful painted coffins.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

An Irish church where an 800-year-old mummy is reaching out of his coffin as if to shake hands.

The anatomical-pathological collection of a man who changed surgery.

English antique dealers with a taste for the unusual.

After nearly 60 years, there's still a bear at Paddington Station looking for help.

A statue marks the exact spot where The Boy Who Never Grows Up made his first literary appearance.

The ruins of this medieval castle in Northern Ireland have inspired artists from C.S. Lewis to Led Zeppelin.

A meandering boardwalk across the bogland leads to a "stairway to heaven" with sublime views.

Celebrated in poem, this tiny hidden cemetery has a big and grisly history.

The last Victorian market in Belfast.

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

The highest peak in Northern Ireland is topped with a stone tower and haunting burial mounds.