A gothic church spire sits atop this skyscraper, the tallest church in the world.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

Inside the Wayne County airport is an amazing collection of lights and sounds.

Controversial tribute to the heavyweight champion boxer who grew up in Detroit.

To truly appreciate Detroit's landmark skyscraper, you have to step inside.

This feline raises a friendly paw at drivers barreling toward the freeway.

A Beaux-Arts triumph rises from decades of decay to become the heart of a new innovation district.

A castle perched precariously over the Crimean Sea.

Legend has it that any woman who kissed this statue would soon be married.

Destroyed numerous times, this centuries-old bridge has always been rebuilt with its original design.

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

A massive bridge forms part of an aqueduct that was deemed an architectural wonder of its time.

This medieval city gate is now a blend of the past and the modern world.

Featuring the last fully walkable parapet walkway in Europe.

One of the highest mountain passes in Europe has been ranked among the best driving roads in the world.

This military mausoleum captures the solemn grandeur that most memorials only aspire to.

In a city that boasts four separate inclined cable railways, this is one of the busiest funicular lines in the world.

Bell tower juts out from a village buried under a lake.

Ancient snack bar of the Roman Empire re-opened.

An underground paleo-Christian burial site composed of the remains of several cemeteries and Basilicas.

Pilgrimage site for star-crossed lovers.

Dug as a secret royal escape route, the tunnel became a wartime bomb shelter and dumping ground for vintage cars.

This shining multicolored metro station deep under Naples is said to be the most beautiful in Europe.

A labyrinth of ancient tunnels hidden below the city holds the ruins of 2,500 years of history.