Humble beginnings for one of the world's most famous scientists.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

A musical instrument played by the sea.

Now harmless, this looming post struck fear into the heart of medieval troublemakers.

The big toe of this towering monument to a Croatian national hero is worn from years of superstitious rubbing.

Longest fortress system anywhere in Europe.

The graffiti-covered remnants of a former triangulation station are balanced precariously on this California peak.

This snug medieval lane is one of the narrowest streets in the world.

The preserved arm of a third-century sorcerer is believed to have the power to lift curses and spells.

The Natural History Museum that time forgot.

No one knows who built this strange cave of worship or exactly why.

This once-derelict building is now one of the most beautiful bookstores in the world.

This massive underground salt mine now holds a sci-fi theme park in its depths.

This elaborately decorated, fairytale-like Romanian royal palace is one of the most striking castles in Europe.

A landscape decorated with enormous skull sculptures.

Historic medieval fortified city in southwest France.

Green labyrinth formed by a karstic maze hidden in a preserved oak forest.

Trek into the depths of the cave where 17,000-year-old paintings exist alongside 400-year-old graffiti.

The Swedish flag over this small naval fort signals that the nation is at peace.

The library's graceful rotunda is like a bibliophile's temple.

An illuminated manuscript comprising the life's work of a lone monk, inexplicably decorated with a portrait of Satan himself.