Rare collection of medieval books under lock and key.

Go deep down into the earth to experience the world of Welsh coal miners.

An 18th century monument regularly tagged with unsettling graffiti referencing a 1940s unsolved murder.

This legendary stone is of unknown origin, and throughout history has been a literal touchstone for British leaders.

The real life town from the Pied Piper of Hamelin has a mechanical puppet show that retells the famous story many times a day.

"The most colorful grottoes of the world.

The history of German architecture is explored across this fairy-scale mini-city.

This historic stone bridge has an entire neighborhood clinging to its sides.

The world's first zoo for microbes collecting the horrible and wonderful things living on and around us.

This Netherlands museum holds a gloriously mechanical collection of ornate musical automata.

A historic observatory now an astronomy museum beautifully situated at the moat of the Middle Age city centre.

This collection of solar timekeepers includes the world's first digital sundial.

Each time a baby is born in Ghent, these streetlights flash in silent celebration.

This narrow Ghent alleyway is an officially sanctioned street art tunnel.

Part modern art project, part traditional chapel, this see-through church is only substantial from the right angle.

This impressive collection of skulls and bones was gathered by an ex-zookeeper who took advantage of a pig plague.

This annual Belgian water race attracts bathtub captains from all over the world.

A 14th-century fortified keep showcases the masterpieces of an ingenious 20th-century clockmaker.

The "stairway to heaven" lookout tower was built to resist weather, arson, and the laws of physics.

A giant bug impaled on a 75-foot-tall needle.

Dummies recreate radiological discoveries from history.

Theme park featuring miniature replicas of European monuments.

This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."

Meet the bronze beloved pet to a family of famous peeing statues.