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

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

Lucerne's central prison was converted into a tourist hotel with a bare minimum of changes.

Northern Ireland's Brobdingnagian stepping stones.

These murals stand as reminders to the troubled history of this Northern Ireland city.

A 600-year-old mini shrine guarded by a sword-wielding knight hides in a crumbling cliff face.

Once thought to be the mysterious work of a witchy prophetess, a well with unusual properties turns objects into "stone".

A miniature village mimics the surrounding buildings so well it includes itself.

A petite castle folly in the English countryside.

Grab a cuppa at England's first and only domestic tea plantation.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

An intricately decorated tiny place of worship.

Underground hospital complex constructed by slave laborers during the German occupation of the Channel Islands.

One of the world's smallest prisons boasts just two small cells.

The first island in the world designated a light-pollution-free astronomical observation point.

A passage grave used in neolithic rituals.

An effigy of a trapped paratrooper dangles from a Normandy church to commemorate one remarkable D-Day event.

This obscene artwork on the side of a newspaper office pokes fun at a rival paper's former editor-in-chief.

What started as a tongue-in-cheek shrine is now a full-blown museum celebrating "The Hoff" and his longtime love affair with Berlin.

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

This easily overlooked memorial immortalizes the scars from the 1956 Hungarian Revolution.

This quiet, unassuming spot in Budapest was the birthplace of the bloody 1956 Hungarian Revolution.

A Trabant car, a kangaroo statue, and a plethora of plants take over this abandoned-factory-turned-bar.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.