This castle-fortress is a living example of the transition from medieval defenses to modern fortifications.

The world's largest solar furnace uses 10,000 mirrors to concentrate the sun's rays to generate power.

The site of the first medieval crusade that pitted Christians against Christians.

Immortalized by artists, this church incorporates a medieval lighthouse into its shoreside structure.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

CERN's beautiful, bending sculpture is a tribute to the spread of knowledge.

An early masterpiece of Le Corbusier, a famed Modernist architect, hiding in plain sight.

Where two rivers meet—but don’t mix.

This colorful but controversial ceiling has been likened to a 21st-century Sistine Chapel.

These traffic lights celebrate the 100 year anniversary of the women's suffrage movement in Lithuania.

A miraculous three-handed portrait of a saint can be found inside this church.

Rub it for a bit of good luck.

A 15-foot-tall statue of the head of the Sopranos family greets passengers at a train station in southeastern Lithuania.

Plaques celebrating Lithuanian writers freckle a wall of this picture-perfect path.

A unique, playful portrayal of Jesus as a backpacking traveler.

The Frank Zappa fan club erected this monument to their prog-rock hero to mark a new era of post-Soviet Lithuania.

Travelers who fall victim to this mermaid's charms are destined to stay in Užupis forever.

A wide array of locomotives call this outdoor museum home.

An angel that hatched from an egg!

A 300-kilogram egg sculpture that embodied a neighborhood revival.

While this monument tile is shrouded in mystery it also marks the end of the longest ever human chain.

This former KGB building is now a museum memorializing the people who suffered during the Soviet regime.

A century-old prison in the heart of Vilnius is now a lively bar, dance club, and artist residency.

An abandoned masterpiece of Soviet Brutalist architecture.