This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

Hidden beneath the streets of London is a secret subway that only carried mail.

A kaleidoscopic warehouse-maze of handmade neon signs.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.

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 ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

Museum dedicated to the terror regimes of Hungary.

This off-beat, quirky communism-themed bar isn't afraid to poke fun at its history.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.

An overgrown and largely forgotten cemetery lies hidden within the outskirts of Amsterdam.

A rare tour of an aristocrat's private home reveals valuable 17th-century paintings from artists like Rembrandt.

An ancient passage filled with stalls selling used books, once frequented by Vincent Van Gogh.

Three connected pink triangles memorialize persecuted gays and lesbians throughout history.

The largest collection of handbags in the world, the oldest of which were used to carry Bibles, primarily by men.

This gorgeous reading room houses the oldest and largest art history library in the Netherlands.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.

The attic of a four-century-old canal house hides a clandestine church.

Established in 1638 to battle the Black Death, Hortus Botanicus Amsterdam is a treasure trove of rare flora.

A floating cat sanctuary on an Amsterdam canal.

Cat art as far as the eye can see.