This psychedelic tromp l'oeil seems to be beckoning drivers to crash into a wall.

This titanic steel chain linking two buildings was installed without permission but instantly beloved.

The world's largest fire hydrant is supposedly tornado-proof.

This woodland architectural installation acts as a camera obscura for the heavens.

Heron, whitewater rapids, and urban industrialism all add to the beauty of this concrete nature walk.

This 29-ton granite ball spins around at the slightest touch thanks to a scientific phenomenon.

This narrow canyon has been carved by the river over thousands of years into spectacular and curious forms.

This historic mansion was built as a symbol of love between a husband and wife.

The flower-shaped temple in Virginia aims to transcend the boundaries of the world’s religions.

This former prison is an Art Deco masterpiece with a past full of civil rights flashpoints.

This fairytale-inspired cottage was created by a university literature professor.

A perfect circle of 24 mysterious holes dates back to prehistoric times.

Over 120,000 curious objects that have shaped our modern world.

St Bernard de Clairvaux Episcopal Church, better known as one of the oldest European buildings in the Western Hemisphere.

Hundreds of glow-in-the-dark objects light up a museum in a historic zinc mine.

The internal railway of one of the biggest steel plants in America has been transformed into a linear park with unique industrial views.

An 18th-century Spanish watchtower made entirely of seashell and concrete.

A luxurious 1880s hotel with its fair share of Tiffany stained glass, Edison electricity, and of course, ghosts.

St. Augustine's record-setting narrow street was designed to protect against pirates.

A tribute to Ponce de Leon's supposed quest for eternal youth.

In this case, 'zero' marks the spot where the iconic Old Spanish Trail ends.

This beautiful example of Victorian engineering is the oldest water-balanced funicular anywhere in the world.

A rotating bridge that carries a little canal over a larger one.

This charming railway is one of the oldest and steepest funiculars in England.