Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

This cemetery features modernist statues as strange as its name.

A beautiful but toxic fountain of mercury.

This semi-secret storybook hedge maze is also the oldest garden in the city.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

The oldest bibliophilia club in America, with exhibitions on historic books and graphic arts.

Hidden on two floors of downtown building, the library has an incredible deal on rent.

The peaceful space is adorned by paintings by the famed abstract artist Mark Rothko.

The fading, forgotten remains of a once bright and booming factory.

Tubing through a cave lit with glowworms is a magical underground experience.

This colorful creation wasn't always a welcome part of Toronto's Moccasin Trail Park.

Rippling sand dunes frozen in the Arizona rock.

An exquisite tunnel of cascading flowers.

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

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

A 6th-century stone lies at the site of the mythical battle waged between King Arthur and his nemesis Mordred.

Despite not growing anywhere near New York City, bananas are ripened in a pressurized room in the Bronx using precise banana science.

This collection of solar timekeepers includes the world's first digital sundial.

Stripes of flowers bloom each spring in a 50 acre rainbow of color.

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

Each year these high desert hills are absolutely covered with poppy flowers in a surreal show of nature.

Under the right circumstances, this waterfall in Yosemite briefly turns a luminescent fiery orange.