This 13th century Gothic brick castle is the largest in the world by surface area.

A floundering Polish shipyard was once the soul of the Solidarity movement that capsized communism.

This centuries-old wooden wonder was built in less than a year and is one of Europe's largest timber-framed churches.

These massive moving sand dunes have swallowed an entire village and are still on the run.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

A fairytale Gothic castle steeped in Nazi treasure conspiracy theories.

The site of the first battle of World War II.

Real bones which are said to have belonged to a Polish dragon.

This fortress dates back to the 6th century and is also the site of a controversial abandoned restoration project.

A solar-powered primary school inspires hope and experimentation in a country ripe for energy innovation.

The Siege of Naarden ended in 1814, but the cannonballs embedded in the town church remain.

At the base of this tower, a plaque marks the original center point of the Netherlands.

The works of poetry's biggest names grace the walls of the city of Leiden, all carefully painted by hand.

This historical Netherlands fortress still bears the marks of its single siege.

Birthplace of the "Cat in the Cradle" and a cluster of iconic, original windmills that let the Dutch tame the seas.

At more than 5,000 years old, these structures are among the oldest free-standing stone buildings in the world.

This spectacular dome managed to survive after being bombed in World War II, in an event known as the "Miracle of Mosta."

The remains of a 1st-century aristocratic Roman town house featuring beautiful well-preserved mosaics.

The floor of this spectacular Baroque sanctuary is covered in memento mori.

This subterranean necropolis holds three floors of antler-dug grave caves.

Burial grounds for more than 1,000 bodies deep under the modern town of Rabat.

Stone Age solar temple is aligned with the sun on each equinox and solstice.

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

This striking icon of the disputed Republic of Artsakh caused a stir at a Eurovision Song Contest.