Legend has this precariously placed rock was placed by giants. Science has another explanation.

Collection of nearly 500 concrete figures sculpted by the late Veijo Rönkkönen.

This neon blue river gets its color from a unique mix of bacteria and volcano minerals.

With well over 130 falls and cascades to brag about, Hamilton, Ontario has earned its stripes as the waterfall capital of the world.

This fantastical waterfall is hidden in a cave located in a cracked cliff.

The once forbidden "secret cabinet" of erotic art from excavations of Pompeii and Herculaneum.

Pompeii's less famous neighbor is still revealing her secrets.

The eccentric home of Estevão Silva da Conceição, known as the "Brazilian Gaudí."

Elaborate tile work in this railway station tells the story of Portugal.

The bizarre visions of H.R. Giger, tucked away in a Swiss medieval city.

One of England's most famous churches hides a pair of little known architectural treasures.

Started as a kitchen garden, now the second largest botanical garden in the world.

This massive concrete sculpture is said to be the heaviest communist monument on Earth.

Thanks to its heroic service during WWII this Soviet castle has been turned into a monument towered over by a brutalist titan.

An abandoned saucer-shaped monument in the Bulgarian mountains.

Underwater art project will double as a massive artificial coral reef to help regenerate the damaged ecosystem.

Handsomely crafted representations of our round planet.

The beautiful baroque library of the Hapsburg empire.

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

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

The Bloemen Route, or “Flower Route”, stretches 25 miles through prime Dutch tulip country as a result of “tulip mania,” the world’s first economic bubble.

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

The crypt of the imposing Stephensdom holds royal intestines and thousands of skeletons.