Hidden in the hills of Hollywood, this secluded Oz-themed garden is dotted with dozens of thrones.

One man's homage to the sun continues to grow like a glass fractal.

America's most famous piece of self-built architecture.

High on a hill overlooking Los Angeles lives a world famous, high power conical Tesla Coil.

The abandoned zoo enclosures offer a perfect place to experience the other side of the bars.

The legendary building that needed ghostly approval before being built.

One of a series of no-purpose kinetic artworks by Swiss sculptor Jean Tinguely.

Despite being considered a thoroughly American sport, basketball's oldest surviving playing field is found in the basement of a Paris YMCA.

Architect Le Corbusier built his friend a cubist house to match his impressive collection of cubist art.

The former home of France's controversial pop maestro is almost completely covered in ever-changing tributes and graffiti.

Hidden away in a modern library are the remains of one of the 18th century's most celebrated wunderkammers.

This banal Parisian entranceway is not what it seems.

A unrivaled and rather horrifying collection of wax dermatological models.

A museum on the history of Paris, including a set of Napoleon's toiletries, Proust's room, and relics of the Revolution.

Exquisite wall sculptures carved in secret by an early quarryman in an obscure corner of the Paris Catacombs.

A subterranean shelter remains intact under a busy Paris railway station.

Down a cobblestone alleyway is a museum dedicated to Romanticism, with a secret garden.

Egyptian Revival movie palace abandoned for decades and restored in 2013.

An abandoned textile factory on the "island of crows" was home to Estonia's first workers' strike.

Two old windmills got a new life as oversized sculptures of a man and a woman.

This Estonian watchtower looks like a big tree with two giant bird nests on it, complete with a "golden egg."

This abandoned office building is a lasting example of Soviet-era architecture.

The widest natural waterfall in Estonia is a sight to see in all seasons.

A wooden replica of France's famous tower.