Hundreds of secret cabinets built into the walls of legendary poisoner's private work room.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

This former “ante-chamber to the guillotine” has been refurbished to illustrate the brutal history of French justice.

Site of a classic 19th-century physics experiment to prove the earth is rotating.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

The celebrated eyesore created by starry-eyed sweethearts.

France's most famous cemetery, with some of its most curious tombs.

A hugely vast Irish landscape of barren rock that stretches for miles.

The ruins of an 800-year-old monastery boasts the tallest round tower in Ireland.

The ancient tomb acts as a calendar that keeps perfect time.

There might not be much left of these Irish ruins, but their linguistic legacy is still going strong.

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

This ancient Irish tower could easily have stood in for Rapunzel's prison.

An ancient neolithic tomb that only sees the sun twice a year.

The oldest inn in Kilkenny was established by the first convicted witch in Ireland.

See some of the world's greatest racing horses at this idyllic thoroughbred breeding facility and garden complex.

Major tourist destination known for its bubbling mud-pools and hot thermal springs.

In the land of the Light Brigade stands a testament to the Cold War.

A castle perched precariously over the Crimean Sea.

The deepest metro station in the world.

Come for the flowers, stay for the bats!

An unphotographable nightly march of tens of thousands of "fairy penguins" from sea to shore.

These mythological giants take time out of their busy day guarding a Victorian market to let you know what time it is.

Think you have a tough job? Try carrying 200 kilos through a cloud of sulfur down the side of a volcano.