Nine centuries-old fortresses guard the walls of this medieval Romanian city.

This hauntingly beautiful cemetery outside a medieval citadel is full of winding paths and ivy-covered graves.

Time stands still at this serene burial ground in the center of Budapest.

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

Once the home of a hermetic monk, this cave now houses a small church.

One of the largest barracks of the Austro-Hungarian monarchy's military is now an abandoned ruin.

The abandoned military base looks like a post-apocalyptic wasteland.

A Dutch passageway's artistic, aquatic-themed makeover pays tribute to the capital city's famed waterways.

Amsterdam's former hotspot for public executions and dissections.

Some 80,000 Delft Blue tiles line the inside of this Amsterdam walkway.

Where royalty waits in the height of luxury.

Unsurprisingly, Holland is home to one of the most magnificent flower gardens in the world.

The European equivalent of the Hollywood Walk of Fame is slowly spreading over the entire city.

This hotel was once home to a steamliner company and became the final rest stop for Europeans heading to the New World.

A bridge that has seen many reiterations over its lifetime.

An icon of International Style architecture on the outskirts of Rotterdam.

The Netherlands' first car tunnel has an unusually rectangular shape.

A condensed piece of China floating in a Dutch harbor.

An early 19th-century English style garden hidden in the Rotterdam cityscape.

A nearly 25-foot concrete sculpture of Sylvette, Picasso's muse.

This charming pup is meant to celebrate the youth and stubbornness of the city's students.

Rotterdammers' dirty minds gave this santa a dirty nickname and cursed it to a life of wandering.

A huge teapot illuminates a home for the elderly.

Four giant movable street lights decorate this modern Rotterdam square.