This arch granting triumphal entrance into Antalya was designed to honor the emperor's visit.

Rare karst landscape eroded from a flat seabed.

Spanish architects used seized Muslim gravestones to rebuild parts of the fortress.

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

Spain's largest bullring offers a unique glimpse at architecture and history.

The world's largest wooden structure.

A curious carving hides on a marble column in the Mosque-Cathedral of Córdoba.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

One of the most spectacular bridges in Spain spans a narrow chasm that divides the city of Ronda.

Three bridges and one giant canyon make up this fantastic Spanish settlement.

Hamburgers are intensely proud of their tunnel beneath the river.

Cold war icon and onetime "hole" in the iron curtain.

This museum tells the story of lake dwellers from 4000 BC to 850 BC, replete with stilt houses and goats.

Soaring over 6,000 feet in the Bavarian Alps, this beer garden was once Hitler's 50th birthday present.

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

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

Started as a kitchen garden, now the second largest botanical garden in the world.

This bridge's unique architecture honors nautical heritage and encourages self-awareness.

The original home of the Lego has a huge amusement park dedicated to the iconic plastic toy.

Denmark’s never-ending bridge.

This colorful artistic feature atop a Danish art gallery allows visitors to stroll through a rainbow.

A walkable map of the world, made from soil and stone by one man.

This Danish rock field is actually a sprawling ancient cemetery holding the bodies of 700 Vikings.

An abandoned lighthouse awaits its destiny: being buried under shifting sand.