Hamburg's first legal sex work is relegated to a gated street that still does not allow pedestrian women.

Hamburgers are intensely proud of their tunnel beneath the river.

Once the tallest building in the world, this abandoned church is now a monument to the destruction of WWII.

Hidden beneath a beautiful overlook you’ll find the history of the city depicted in comic strip format next to a pay toilet.

Legend has it that Napoleon Bonaparte fell in love with this Gothic church.

Made famous by 'Star Wars,' these troglodyte homes face an uncertain future.

An ancient burial ground believed to have been used for ritual sacrifice.

One man's remarkable private collection of art from around the world.

Ring the bell to enter a bar that looks equal parts museum and old curiosity shop.

This once-forgotten oasis in the middle of Lisbon was first created over a century ago quite by accident.

If you visit Santa's village, you can get your passport stamped to show you crossed into the Arctic Circle.

A lush indoor jungle fills this bustling Madrid transportation hub.

The walls and streets of the ancient city are peppered with penises.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

An artificial date palm stands as a memorial to Warsaw's Jewish community.

The Polish capital has had a deep connection to its guardian mermaid for almost a millennium now.

The largest Art Nouveau complex in the world is a Barcelona hospital with a 600-year-long history.

In Portugal, a secluded stretch of untouched natural beauty hides at the bottom of a steep hill.

Portugal's National Pantheon has a history of curses, collapses and financial problems.

The "Little Ones," show Portugal in full miniature splendor.

One of the smallest bookstores on the planet.

At night, bats patrol this magnificent 18th-century space in search of book-eating pests.

Perhaps the tiniest sculpture in Saint Petersburg is a little bronze finch inspired by a song.

This cathedral hides a sculpted dog that determines your fate and an unexploded shell from World War II.