The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

This unassuming museum's slogan translates to “there is a limit of sadness, anxiety has no limits."

This attraction was abandoned after the Chernobyl disaster.

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

Man-made mineral caves house massive bat colony.

In oil-rich Azerbaijan, people bathe in the black stuff.

Azerbaijani ghost town, decaying after a war left it an armed forces buffer zone.

Swirling layers of white and red rock earned these mountains their festive nickname.

Resonant stone, that has been played since prehistoric times.

This striking icon of the disputed Republic of Artsakh caused a stir at a Eurovision Song Contest.

A fiery crater has been burning in the Karakum Desert since 1971.

These gigantic skeletons tower over visitors and provide insight into the creatures that once ruled over Ireland.

The Grand Lodge of Ireland is one of the oldest in the world, full of fantastical, elaborately themed rooms.

This permanent collection of preserved bodies taken from Irish bogs is one of the leading authorities on such morbid mummies.

Inside this mansion turned museum, the works of prominent Croatian artists are on full display.

A temple to modernity, tucked away amid Barcelona's more well known museums.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

An eclectic collection of thousands of items owned by the sculptor Frederic Marès.

An unusual stroll through gentlemen's erotica demonstrates that pornography is timeless.

This cemetery features modernist statues as strange as its name.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

A celebration of all things tacky, garish, and bizarrely creative in the Romanian capital.

A modern-day cabinet of curiosities housed in a 300-year-old inn.