Roman ruins top white travertine terraces formed by ancient hot springs.

In this historic region, homes and churches are carved into ancient volcanic rock formations.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

It houses the remains of a 17th-century version of the Titanic.

The spot where the fascist dictator made some of his most famous speeches including declaring war on Britain and France.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

Pilgrimage site for star-crossed lovers.

The wreckage of a tragic plane crash is on display at this museum devoted to a famous Italian conspiracy.

A small window on Via Piella offers a lovely and rare peek at Bologna's lost canals.

Legend has it this fountain built to symbolize the Pope’s power hides a strange secret concerning Neptune's manliness.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

This bronze boar's snout has been rubbed to a golden sheen by visitors seeking good fortune.

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

A statue in Budapest's Liberty Square honors the former U.S. president's efforts to end the Cold War.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

The former private quarters and office of Dr. Sigmund Freud now hosts a museum housing the works of the founding father of psychoanalysis.

Beautiful Austrian natural history museum with carved ceilings and row after row of ancient taxidermy.

This Slovak bridge is known both for its connection to a national uprising and its UFO-shaped eatery.

This Slovakian statue of an emerging sewer worker might just be a bronze peeping tom.

The palace window through which Protestant nobles flung two Catholic regents, thus sparking the Thirty Years' War.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.