Ancient cliffs resembling a kilt on Scotland's second largest island emit an entrancing sound.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

Walk inside a half mile long crevice right outside the town of Garmisch Partenkirchen.

Twisted trees shaped by coastal winds make this woodland look like something from a spooky story.

This riverside restaurant has been serving customers since 1146.

You haven’t properly toured a winery until you’ve slept in an actual wine barrel.

The last remnants of a massive medieval wall that once encompassed the city of Berlin.

Dress up like a miner and take a slide into the disco-lit depths of this once foundational salt mine.

This museum tells the story of lake dwellers from 4000 BC to 850 BC, replete with stilt houses and goats.

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

These 18th century gardens tell a rocky story of the son of Odysseus.

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

A long spiraling walkway winds through the woods, and around a copper beech tree at the center.

When the rain falls, this drain system turns into a musical instrument.

Soaring over 6,000 feet in the Bavarian Alps, this beer garden was once Hitler's 50th birthday present.

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

A stairway to heaven, or to nowhere at all.

"The most colorful grottoes of the world.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

A beer pipeline runs beneath Bruges.

A Museum of Psychiatry in a still-operating mental institution.

The entrance to this Frankfurt subway station looks like an old tram car crashed into the concrete sidewalk.

Fantastic views and thousands of love locks.