The largest bottled beer collection in the world holds over 22,000 unique beer bottles.

A 19th-century subterranean reservoir repurposed as a contemporary art cave.

Copenhagen's celebrated theme park and gardens.

This pair of gilded girls atop an Art Deco building in Copenhagen were built to function as a weather indicator.

Six beautiful wooden giants are hidden around Copenhagen.

A ceramic postbox where visitors can post original poems and creative messages.

Glasgow’s piece of the patron saint of love.

The abandoned transportation hub hides within the Glasgow attraction it once served.

Houses are tucked between, on, and underneath giant boulders.

Ring the bell to enter a bar that looks equal parts museum and old curiosity shop.

This gaping hole in the middle of a remote mountain lake looks like a portal to another dimension.

The best place in the world to buy tinned fish.

One of few vertical lava tubes in the world accessible by foot.

"Portugal's Stonehenge" is made up of nut-like stones aligned with the heavens.

The verdant mossy ruins of a Franciscan monastery lie in the remote Sintra hills awaiting exploration.

Perhaps the most spectacular grotto along the Algarve coastline.

A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

The extravagance of Portugal’s "Pink Palace" resulted in a noble title being awarded to its owner.

A 15th-century whalebone is tucked away in an unassuming corner of this medieval church.

A miniature replica of the canine that became the logo for a large recording company.

Ornamented with "Bristol Diamonds," this exotic shell grotto is considered to be the finest surviving example from the eighteenth century.

One of Bristol's best-hidden gems has ties to Lord Byron, whence it became the nation's first reformatory school for girls.