An imperial church bombed to ruins during WWII now stands as a jagged memorial.

The smaller of the three towers of San Marino is a former prison inaccessible from the ground level.

The former Nazi Germany concentration camp stands as a museum to remember this dark chapter in European history.

Dedicated to the European Sinti and Roma peoples murdered during the Holocaust.

Tiny memorials honor individual victims of the Holocaust.

A Reformation-era fiery figurehead once denoted this location as a print shop.

A large statue of Pope Gregory XIII in Bologna was disguised as Saint Petronius to avoid destruction.

A World War II evacuation tunnel turned into a history display of Croatian state and people.

This platform is now a memorial dedicated to those who were deported during the Holocaust.

An abstract and eyecatching clock/fountain is the centerpiece of this little-known German city.

Stuck in the arcade of Casa Isolani are three arrows of mysterious origins.

The reconstruction of this prominent building fulfilled a long-written command.

Largest lake in Great Britain measured by surface area.

A 200-year-old collection of oddities and medical paraphernalia.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.

This cheese shop also houses a museum devoted to Dutch dairy.

The world's first military tank was designed in this English city amid the stalemate of WWI trench warfare.

WWII artifacts, including the building itself.

The remains of the concrete ship can be seen during low tide.

These remarkable cascades are the jewels of Upper Tees.

This building was once a town hall, a fire station, a prison, a dairy market, and the target for two marksmen.

Huge winged monument in the United Kingdom.

The nearly 200-year-old folly has a secret spiral staircase hidden in one of its pillars.

The little-known second castle that William the Conqueror built in York.