A massive marble foot is tucked away in a small alley near the Pantheon.

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

San Gennaro, the patron saint of Naples, greets pedestrians between these narrow city streets.

This bustling Italian plaza is built on the ruins of an ancient Roman amphitheater.

Fortified medieval tower house with lovely roof garden.

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

A striking memorial recalls thousands of Bolognese men and women killed fighting fascists in World War II.

Once known for its horse-powered knife sharpening, this 200-year-old shop offers an array of blades and hard-to-find culinary tools.

The remains of an ancient Roman city are hidden underneath Bologna's beautiful public library.

Pilgrimage site for star-crossed lovers.

Renaissance hospital featuring a rotating door into which unwanted babies were dropped.

This medieval castle was reconstructed by Carlo Scarpa.

An Austrian house of bones filled with hundreds of intricately painted skulls.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.

A vertically floating hemlock controls the waves and weather at Crater Lake.

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

This Arizona observatory is famous for investigations into Martian life, and as the place humans first spotted Pluto.

This public square capitalized on a single Eagles reference to bring some life back to an Arizona town.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

A beautiful geyser under environmental threat.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

This crumbling little graveyard was saved from the undergrowth by concerned veterans.