Rare recess caves fill this unbelievably beautiful Ohio park.

Outstanding, eerie frescoes and decorations fill this 19th-century monastery.

This nonsensical smiling boat shuttles passengers between two places they could've easily walked between.

This spectacular mosque houses the second-largest chandelier in the world.

The lighthouse central to the 1980s horror classic "The Fog" is, in fact, located in one of the foggiest areas of the Pacific Coast.

A statue of the legendary Celtic warrior queen who fought the Roman invaders stands in one of the cities she once destroyed.

William Smith's iconic "map that changed the world" is hidden behind a curtain in the Geological Society building.

Along the most northwestern point in Africa is an ancient cave surrounded by legends.

In a quiet north Chicago neighborhood rests a stunning relic of the golden age of earthenware design.

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

The Neolithic megalith was one of the first archaeological ruins protected by the British government.

This staircase in a lush tropical grotto was built by enslaved laborers and renamed to honor Queen Victoria's role in ending slavery in the British Empire.

A charming 17th-century alley is lined with secondhand bookstores and antiquarian shops.

These magnificent city walls rise from the barren sun-baked Spanish plains like something straight out of a fairytale.

Saved by a logger, this Douglas fir is one of the last great old-growth trees in Canada.

Cornish legend says these ancient circles were people turned to stone for playing hurling on a Sunday.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

This ruined 15th-century hermitage is steeped in myth and mystery.

At this deceptively beautiful beach, nothing is what it seems.

Though its celestial ceiling is impressive, the true star is the vast collection of French books.

Tucked along a river are enigmatic stone carvings created thousands of years ago.

This nomadic monster has divided opinions as it prowls across Canada.

The fierce beast perches atop a pedestal marking where the historic City of London gates once stood.

This strange sculpture of a menacing skull surrounded by sun rays was discovered at the foot of the Pyramid of the Sun.