Thousands of flowers create enchanting pink tunnels over the city streets.

The largest bell in the world has been swinging high above a Cologne cathedral for almost a century.

No need to strap in for a "ride" on this walkable roller coaster.

Theme park featuring miniature replicas of European monuments.

Climb inside an iron crystal magnified 165 billion times its normal size.

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.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

Christ's blood preserved in a Belgian town.

Three floors of musical instruments coming from all corners of the world and hundreds of years of musical history.

Cozy basement bar sports an inventory of over 2,000 beers.

The Devil’s own choice when he needs a drink in Brussels.

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

This former steel and coal plant is now a neon-lit industrial fantasia.

This "floating railway" is one of the world's oldest monorail systems.

This painted Lego bridge is the product of over a century of locomotive history.

A church filled with the bones of hundreds of virgins martyrs—or so they say.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

This massive library holds what was once the largest book collection in the world.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

A little sculpture with a large wardrobe.

The alleged house of the Virgin Mary is tucked away in a park and nature preserve on Mt. Koressos in Turkey and is holy to both Catholics and Muslims alike.

Roman ruins top white travertine terraces formed by ancient hot springs.