19th century pendulum and a clock restored by a rogue group of guerilla artists.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

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

Berliners converted a bombed-out, disused lot into a community-run urban farm with its own cafe and bar.

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

Berlin's old airport.

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

The most visited, and possibly most controversial, museum in Germany.

The attic of a four-century-old canal house hides a clandestine church.

A replica of a beloved, delicately-balanced granite boulder.

A small but industrious mining operation that allows visitors to touch precious gems while they are still in the rock.

The most southern point you can drive to in the Western Hemisphere.

A series of waterfalls so massive they straddle the border of Argentina and Brazil.

This stunning mass of ice spans 121 square miles and is still growing.

This sweet-toothed bear searching for snacks has been a symbol of Madrid for decades.

Among the oldest structures in Madrid, these Moorish walls once guarded the medieval city of Mayrit.

Giant topiary dog once played a role in a terrorist bomb plot.

A stone slab in Madrid marks the point from which the distances of Spain's national roads are measured.

The oldest Roman lighthouse still in use.

These magnificent city walls rise from the barren sun-baked Spanish plains like something straight out of a fairytale.

The final resting place of the great navigator, or maybe his brother.

A lush indoor jungle fills this bustling Madrid transportation hub.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'