The idyllic island where the philosopher Jean-Jacques Rousseau spent “the happiest time of his life.”

Traversing steep Alpine slopes, this engineering marvel is one of the longest and highest funiculars in the world.

The steepest classic funicular in the world glides along a dizzying incline.

A historic observatory precariously perched at the "Top of Europe."

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

These spooky and unusual stone formations create an underworldly landscape.

This amazing pedestrian suspension bridge in the Swiss Alps would give Indiana Jones nightmares.

Caves famous for the dragon-slaying saint who lived there.

A nearly 500-year-old sculpture depicts a man eating a sack of babies, and no one is sure why.

This lovely little bridge hidden in a Switzerland gorge is essentially a fairytale.

The tallest outdoor elevator in Europe rockets passengers on a dizzyingly precarious ride to the top of a mountain.

This 170-year-old Swiss guesthouse built into the side of a mountain is best accessed by a cable car.

Resting in the middle of an Austrian river, this sci-fi "island" lets people cross in neon style.

Visitors dip into a variety of pools of what was once ice.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

Swarovski's museum/theme park is a fake diamond fantasia overlooked by a giant.

The topiary maze at the Habsburg hunting lodge.

A crumbling World War I fort that is reached through a series of concrete tunnels.

This one-time health resort was used by aristocrats around the world.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

This truly palatial work of Communist-era architecture now sits crumbling on a Croatian beach.

This artificial cave looks like something out of a fairytale.

A plaque marks the spot where the saint was shoved off the Charles Bridge and into the river.

The 14th-century ruins are said to contain healing powers.