Built over an abandoned train yard, this hidden gem is full of winding paths and offers gorgeous views of Sydney Harbour.

A massive stairway that almost wasn't leads to one of Australia's most scenic vistas.

A castle hand-built by a Spanish dreamer in the Australian tropical jungle.

A small, but award-winning beach known for its literally spotless reputation.

This gracefully curving formation looks like a massive wave that was suddenly turned to stone.

An abandoned railroad tunnel is now filled with bioluminescent bugs.

Bask in the 19th century grandeur of an eccentric Freemason millionaire's private gardens.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

Tucked away near more famous landmarks lies a statue meant to symbolize the confluence and continuing development of human culture.

Museum dedicated to the terror regimes of Hungary.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

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

A font of vintage porn on the silver screen.

France's most famous cemetery, with some of its most curious tombs.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

The walls of Germany's Parliament still show the scars of the Red Army takeover in World War II.

When German-Iraqi relations broke down, this embassy was vacated post haste.

The bunker where Hitler took his own life is hidden under this deliberately ordinary parking lot.

An abandoned NSA listening post on Berlin's "Devil's Mountain."

A floating cat sanctuary on an Amsterdam canal.

Established in 1638 to battle the Black Death, Hortus Botanicus Amsterdam is a treasure trove of rare flora.

This classic restaurant features a gorgeous mirror-clad room.

A slice of central Asia in the middle of Berlin.