This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

The world's largest maze is a nature park with nearly 200 decision points.

This colorful artistic feature atop a Danish art gallery allows visitors to stroll through a rainbow.

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

An ultra-modern diversity park in Denmark has turned an entire city block electric pink.

A walkable map of the world, made from soil and stone by one man.

A red sandstone freestanding monolith rises out of the sea in northern Scotland.

Geodesic dome luxury retreat in the Scottish Highlands.

The true age of this ancient stone circle is unknown, but its stunning vista isn't in question.

Largest lake in Great Britain measured by surface area.

Old-fashioned knowledge and modern engineering create the world's only rotating boatlift.

A 30-acre garden inspired by the principles of modern physics.

These fantastically named natural pools look like something out of a Scottish myth.

360° views of the city plus five floors of optical illusions and hands-on science.

There are plenty of wonderful panoramic vistas in Edinburgh, but not many are hidden smack in the middle of the Old Town.

A natural wonder in south Denmark.

Swedish mice can dine at the Nuts of Life restaurant or take a date to the amousement park.

Six beautiful wooden giants are hidden around Copenhagen.

A museum filled with tiny, adorable versions of the mighty Royal Danish Navy.

Hotel designed by indie graphics artists.

This Scottish manor house is a lush relic from the life of a literary great.

The mystery of this small, brick pond eluded its possibly only investigator until his death.

A giant pineapple, a symbol of hospitality, and an amazing vacation rental option.

The heads of two giant mythological water horses honor Scotland's horselord past.