This statue honors the thousands of Allied avians that served and died for France during World War I.

This triumphal arch celebrating the Sun King's conquest of Lille is a masterpiece of military architecture.

Tables of secondhand books fill the inner courtyard of this 17th-century stock exchange.

Lyon's "Wall of the Silk Weavers" is one of the largest murals in Europe.

Lyon, France is home to two remarkably preserved Roman theaters, one dating back to 15 BCE.

Hundreds of hidden passageways weave through the old quarters of Lyon.

A suspended footbridge allows for traversing this gorge carved through the French Alps.

The oldest surviving wooden bridge over Rhine lets travelers cross easily from Switzerland to Liechtensten.

On a small Slovenian island, diners can mix and match a classic cake into dozens of sweet and savory flavor combinations.

A trough of 700 strange bronze faces runs through a narrow alley in Ljubljana's old town.

The "dragon babies" of southeastern Europe.

Martin Bricelj Baraga's monolithic sculpture measures the blueness of the sky, and changes color to match it.

This abandoned Slovenian military barracks has become a punky-political art squat.

A whimsical bridge adorned with decorative dragons.

A miniature train-ride through Slovenia's largest cave system.

This one-time health resort was used by aristocrats around the world.

This massive subterranean fissure is known as the "underground Grand Canyon."

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

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

A wunderkammer of exoticism immortalized by Tom Waits.

Model Trains and Much More in Hamburg.

Executed in 1401, Exhumed in 1878, Stolen in 2010.

Hamburgers are intensely proud of their tunnel beneath the river.

Remnants of an exploded schooner and wrecked submarines form a breakwater.